Year 2000 problem
Encyclopedia
The Year 2000 problem (also known as the Y2K problem, the Millennium bug, the Y2K bug, or simply Y2K) was a problem for both digital (computer-related) and non-digital documentation and data storage situations which resulted from the practice of abbreviating a four-digit year to two digits.
In computer programs, the practice of representing the year with two digits becomes problematic with logical error(s) arising upon "rollover" from x99 to x00. This has caused some date-related processing to operate incorrectly for dates and times on and after January 1, 2000 and on other critical dates which were billed "event horizon
s". Without corrective action, long-working systems would break down when the "...97, 98, 99, 00..." ascending numbering assumption suddenly became invalid. Companies and organizations worldwide checked, fixed, and upgraded their computer systems.
The number of computer failures that occurred when the clocks rolled over into 2000 in spite of remedial work is not known; amongst other reasons is the reticence of organisations to report problems. There is evidence of at least one date-related banking failure due to Y2K. There were plenty of other Y2K problems, and that none of the glitches caused major incidents is seen by some, such as the Director of the UN-backed International Y2K Co-operation Centre and the head of the UK's Taskforce 2000, as vindication of the Y2K preparation. However, some questioned whether the relative absence of computer failures was the result of the preparation undertaken or whether the significance of the problem had been overstated.
and was the common abbreviation for the year 2000 software problem. The abbreviation combines the letter Y for "year", and k for the SI unit prefix kilo meaning 1000; hence, 2K signifies 2000. It was also named the Millennium Bug because it was associated with the popular (rather than literal) roll-over of the millennium
, despite the fact that the problem could have occurred at the end of any ordinary century
.
The Year 2000 problem was the subject of the early book, Computers in Crisis by Jerome and Marilyn Murray (Petrocelli, 1984; reissued by McGraw-Hill
under the title The Year 2000 Computing Crisis in 1996). The first recorded mention of the Year 2000 Problem on a Usenet
newsgroup occurred Friday, January 18, 1985 by Usenet poster Spencer Bolles. Another possible early reference is the Cleveland band Pere Ubu
's 1978 album Datapanic in Year Zero. The singer's father was a computer professor.
The acronym Y2K has been attributed to David Eddy, a Massachusetts programmer, in an e-mail sent on June 12, 1995. He later said, "People were calling it CDC (Century Date Change), FADL (Faulty Date Logic) and other names."
Many computer programs stored years with only two decimal digits; for example, 1980 would be stored as 80. Some such programs could not distinguish between the year 2000 and the year 1900. Other programs would try to represent the year 2000 as 19100. This could cause a complete failure and cause date comparisons to produce incorrect results. Some embedded system
s, making use of similar date logic, were expected to fail and cause utilities and other crucial infrastructure to fail.
Some warnings of what would happen if nothing was done were particularly dire:
Special committees were set up by governments to monitor remedial work and contingency planning, particularly by crucial infrastructures such as telecommunications, utilities and the like, to ensure that the most critical services had fixed their own problems and were prepared for problems with others. While some commentators and experts argued that the coverage of the problem largely amounted to scaremongering, it was only the safe passing of the main "event horizon" itself, January 1, 2000, that fully quelled public fears. Some experts who argued that scaremongering was occurring, such as Ross Anderson, Professor of Security Engineering
at the University of Cambridge Computer Laboratory
, have since claimed that despite sending out hundreds of press releases about research results suggesting that the problem was not likely to be as big a problem as some had suggested, they were largely ignored by the media.
and punched card
s, most commonly the 80-column variety employed by IBM, which dominated the industry. Many tricks were used to squeeze needed data into fixed-field 80 character records. Saving two digits for every date field was significant in this effort.
In the 1960s, computer memory and mass storage were scarce and expensive. Early core memory cost one dollar per bit. Popular commercial computers, such as the IBM 1401
, shipped with as little as 2 Kbytes of memory. Programs often mimicked card processing techniques. Commercial programming languages of the time, such as COBOL and RPG, processed numbers in their character representations. Over time the punched cards were converted to magnetic tape and then disk files, but the structure of the data usually changed very little. Data was still input using punched cards until the mid-1970s. Machine architectures, programming languages and application designs were evolving rapidly. Neither managers nor programmers of that time expected their programs to remain in use for many decades. The realization that databases were a new type of program with different characteristics had not yet come.
There were exceptions, of course. The first person known to publicly address this issue was Bob Bemer
, who had noticed it in 1958 as a result of work on genealogical software. He spent the next twenty years trying to make programmers, IBM, the U.S. government and the ISO aware of the problem, with little result. This included the recommendation that the COBOL PICTURE clause
should be used to specify four digit years for dates. Despite magazine articles on the subject from 1970 onward, the majority of programmers and managers only started recognizing Y2K as a looming problem in the mid-1990s, but even then, inertia and complacency caused it to be mostly unresolved until the last few years of the decade. In 1989, Erik Naggum
was instrumental in ensuring that Internet mail used four digit representations of years by including a strong recommendation to this effect in the Internet host requirements document RFC 1123.
Saving space on stored dates persisted into the Unix era, with most systems representing dates to a single 32-bit word, typically representing dates as elapsed seconds from some fixed date
.
.
The main source of problems was confusion between hexadecimal number encoding and Binary-coded decimal
(BCD) encodings of numbers. Both hexadecimal and BCD encode the numbers 0–9 as 0x0–0x9. But BCD encodes the number 10 as 0x10, whereas hexadecimal encodes the number 10 as 0x0A; 0x10 interpreted as a hexadecimal encoding represents the number 16.
For example, because the SMS protocol uses BCD for dates, some mobile phone software incorrectly reported dates of SMSes as 2016 instead of 2010. Windows Mobile
is the first software reported to have been affected by this glitch; in some cases WM6 changes the date of any incoming SMS message sent after 1 January 2010 from the year "2010" to "2016". It has been said that this tends to affect phones on the CDMA network (not using SIM cards).
Other systems affected include EFTPOS
terminals, and older Sony PlayStation 3 models (except the Slim).
The most important such glitch occurred in Germany, where upwards of 20 million bank cards became unusable, and with Citibank Belgium, whose digipass customer identification chips stopped working.
, the largest number representable by a signed 32-bit integer, causing the Year 2038 problem
(also known as Unix Millennium bug, or Y2K38). To solve this problem, many systems and languages have switched to a 64-bit timestamp, or supplied alternatives which are 64-bit.
; minor technological glitches occur on a regular basis. Some caused erroneous results, some caused machines to stop working, some caused date errors, and two caused malfunctions.
Reported problems include:
. The White House
effort was conducted in coordination with the then-independent Federal Emergency Management Agency
(FEMA), and an interim Critical Infrastructure Protection Group, then in the Department of Justice, now in Homeland Security. The Dutch Government promoted Y2K Information Sharing and Analysis Centers (ISACs) to share readiness between industries, without threat of antitrust violations or liability based on information shared.
The U.S. Government followed a three part approach to the problem: (1) Outreach and Advocacy (2) Monitoring and Assessment and (3) Contingency Planning and Regulation.
A feature of U.S. Government outreach was Y2K websites including Y2K.GOV. Presently, many U.S. Government agencies have taken down their Y2K websites. Some of these documents may be available through National Archives and Records Administration
or the Wayback Machine
.
Each federal agency had its own Y2K task force which worked with its private sector counter parts. The FCC had the FCC Year 2000 Task Force.
Most industries had contingency plans that relied upon the Internet for backup communications. However, as no federal agency had clear authority with regard to the Internet at this time (it had passed from the U.S. Department of Defense to the U.S. National Science Foundation and then to the U.S. Department of Commerce), no agency was assessing the readiness of the Internet itself. Therefore on July 30, 1999 the White House held the White House Internet Y2K Roundtable.
, to indicate the century in which a person was born. In both countries the birth year was indicated with two digits only. However, a similar problem already existed, the "Year 1900 problem
", about distinguishing between people born in the 20th or 19th century, so the timing was more because of the Y2K attention than a solution to a new problem. In Finland the problem was solved by replacing the hyphen ("- ") in the number with the letter "A" for people born in the 21st century. In Norway, the range or the individual numbers following the birth date was altered from 0-499 to 500-999.
, the year 1900 problem
and subsequently the Y2K problem were addressed by the use of unused values above 12 in the month range. For all persons born before 1900, the month is stored as calendar month + 20, and for all persons born after 1999, the month is stored as calendar month + 40.
IY2KCC's mission was to "promote increased strategic cooperation and action among governments, peoples, and the private sector to minimize adverse Y2K effects on the global society and economy." Activities of IY2KCC were conducted in six areas:
IY2KCC closed down in March 2000.
The Y2K issue was a major topic of discussion in the late 1990s and, predictably, showed up in most popular media. A number of "Y2K disaster" books were published such as Deadline Y2K by Mark Joseph. Movies such as Y2K: Year to Kill capitalized on the currency of Y2K, as did numerous TV shows, comic strips, and computer games.
called Y2K an "end-of-the-world cult" and the "hoax of the century". The opposing view was bolstered by a number of observations.
In computer programs, the practice of representing the year with two digits becomes problematic with logical error(s) arising upon "rollover" from x99 to x00. This has caused some date-related processing to operate incorrectly for dates and times on and after January 1, 2000 and on other critical dates which were billed "event horizon
Event horizon
In general relativity, an event horizon is a boundary in spacetime beyond which events cannot affect an outside observer. In layman's terms it is defined as "the point of no return" i.e. the point at which the gravitational pull becomes so great as to make escape impossible. The most common case...
s". Without corrective action, long-working systems would break down when the "...97, 98, 99, 00..." ascending numbering assumption suddenly became invalid. Companies and organizations worldwide checked, fixed, and upgraded their computer systems.
The number of computer failures that occurred when the clocks rolled over into 2000 in spite of remedial work is not known; amongst other reasons is the reticence of organisations to report problems. There is evidence of at least one date-related banking failure due to Y2K. There were plenty of other Y2K problems, and that none of the glitches caused major incidents is seen by some, such as the Director of the UN-backed International Y2K Co-operation Centre and the head of the UK's Taskforce 2000, as vindication of the Y2K preparation. However, some questioned whether the relative absence of computer failures was the result of the preparation undertaken or whether the significance of the problem had been overstated.
Background
Y2K is a numeronymNumeronym
A numeronym is a number-based word.Most commonly, a numeronym is a word where a number is used to form an abbreviation . Pronouncing the letters and numbers may sound similar to the full word: "K9" for "canine"...
and was the common abbreviation for the year 2000 software problem. The abbreviation combines the letter Y for "year", and k for the SI unit prefix kilo meaning 1000; hence, 2K signifies 2000. It was also named the Millennium Bug because it was associated with the popular (rather than literal) roll-over of the millennium
Millennium
A millennium is a period of time equal to one thousand years —from the Latin phrase , thousand, and , year—often but not necessarily related numerically to a particular dating system....
, despite the fact that the problem could have occurred at the end of any ordinary century
Century
A century is one hundred consecutive years. Centuries are numbered ordinally in English and many other languages .-Start and end in the Gregorian Calendar:...
.
The Year 2000 problem was the subject of the early book, Computers in Crisis by Jerome and Marilyn Murray (Petrocelli, 1984; reissued by McGraw-Hill
McGraw-Hill
The McGraw-Hill Companies, Inc., is a publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, education, publishing, broadcasting, and business services...
under the title The Year 2000 Computing Crisis in 1996). The first recorded mention of the Year 2000 Problem on a Usenet
Usenet
Usenet is a worldwide distributed Internet discussion system. It developed from the general purpose UUCP architecture of the same name.Duke University graduate students Tom Truscott and Jim Ellis conceived the idea in 1979 and it was established in 1980...
newsgroup occurred Friday, January 18, 1985 by Usenet poster Spencer Bolles. Another possible early reference is the Cleveland band Pere Ubu
Pere Ubu
Pere Ubu is an experimental rock music group from Cleveland, Ohio.Père Ubu may also refer to:* Ubu, the enigmatic central figure of a series of French plays by Alfred Jarry, including Ubu Roi, and subsequent plays Ubu Cocu and Ubu Enchaîné...
's 1978 album Datapanic in Year Zero. The singer's father was a computer professor.
The acronym Y2K has been attributed to David Eddy, a Massachusetts programmer, in an e-mail sent on June 12, 1995. He later said, "People were calling it CDC (Century Date Change), FADL (Faulty Date Logic) and other names."
Many computer programs stored years with only two decimal digits; for example, 1980 would be stored as 80. Some such programs could not distinguish between the year 2000 and the year 1900. Other programs would try to represent the year 2000 as 19100. This could cause a complete failure and cause date comparisons to produce incorrect results. Some embedded system
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...
s, making use of similar date logic, were expected to fail and cause utilities and other crucial infrastructure to fail.
Some warnings of what would happen if nothing was done were particularly dire:
The Y2K problem is the electronic equivalent of the El Niño and there will be nasty surprises around the globe. — John HamreJohn HamreJohn J. Hamre is a specialist in international studies, a former Washington bureaucrat and the current president and CEO of the Center for Strategic and International Studies, a position he has held with that think tank since April 2000.-Education:Hamre is the son of Melvin Sanders and Ruth Lucile...
, United States Deputy Secretary of Defense
Special committees were set up by governments to monitor remedial work and contingency planning, particularly by crucial infrastructures such as telecommunications, utilities and the like, to ensure that the most critical services had fixed their own problems and were prepared for problems with others. While some commentators and experts argued that the coverage of the problem largely amounted to scaremongering, it was only the safe passing of the main "event horizon" itself, January 1, 2000, that fully quelled public fears. Some experts who argued that scaremongering was occurring, such as Ross Anderson, Professor of Security Engineering
Security engineering
Security engineering is a specialized field of engineering that focuses on the security aspects in the design of systems that need to be able to deal robustly with possible sources of disruption, ranging from natural disasters to malicious acts...
at the University of Cambridge Computer Laboratory
University of Cambridge Computer Laboratory
The Computer Laboratory is the computer science department of the University of Cambridge. As of 2007, it employs 35 academic staff, 25 support staff, 35 affiliated research staff, and about 155 research students...
, have since claimed that despite sending out hundreds of press releases about research results suggesting that the problem was not likely to be as big a problem as some had suggested, they were largely ignored by the media.
Programming problem
The practice of using two-digit dates for convenience predates computers, but was never a problem until stored dates were used in calculations.The need for bit conservation
In the first half of the 20th century, well before the computer era, business data processing was done using unit record equipmentUnit record equipment
Before the advent of electronic computers, data processing was performed using electromechanical devices called unit record equipment, electric accounting machines or tabulating machines. Unit record machines were as ubiquitous in industry and government in the first half of the twentieth century...
and punched card
Punched card
A punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions...
s, most commonly the 80-column variety employed by IBM, which dominated the industry. Many tricks were used to squeeze needed data into fixed-field 80 character records. Saving two digits for every date field was significant in this effort.
In the 1960s, computer memory and mass storage were scarce and expensive. Early core memory cost one dollar per bit. Popular commercial computers, such as the IBM 1401
IBM 1401
The IBM 1401 was a variable wordlength decimal computer that was announced by IBM on October 5, 1959. The first member of the highly successful IBM 1400 series, it was aimed at replacing electromechanical unit record equipment for processing data stored on punched cards...
, shipped with as little as 2 Kbytes of memory. Programs often mimicked card processing techniques. Commercial programming languages of the time, such as COBOL and RPG, processed numbers in their character representations. Over time the punched cards were converted to magnetic tape and then disk files, but the structure of the data usually changed very little. Data was still input using punched cards until the mid-1970s. Machine architectures, programming languages and application designs were evolving rapidly. Neither managers nor programmers of that time expected their programs to remain in use for many decades. The realization that databases were a new type of program with different characteristics had not yet come.
There were exceptions, of course. The first person known to publicly address this issue was Bob Bemer
Bob Bemer
Robert William Bemer was a computer scientist best known for his work at IBM during the late 1950s and early 1960s.-Biography:...
, who had noticed it in 1958 as a result of work on genealogical software. He spent the next twenty years trying to make programmers, IBM, the U.S. government and the ISO aware of the problem, with little result. This included the recommendation that the COBOL PICTURE clause
Picture clause
A picture clause is an element in programming languages that is used to describe a datum, by using sample characters that indicate the item characteristics and size.- History :...
should be used to specify four digit years for dates. Despite magazine articles on the subject from 1970 onward, the majority of programmers and managers only started recognizing Y2K as a looming problem in the mid-1990s, but even then, inertia and complacency caused it to be mostly unresolved until the last few years of the decade. In 1989, Erik Naggum
Erik Naggum
Erik Naggum was a computer programmer recognized for his work in the fields of SGML, Emacs and Lisp. Since the early 1990s he was also a provocative participant on various Usenet discussion groups....
was instrumental in ensuring that Internet mail used four digit representations of years by including a strong recommendation to this effect in the Internet host requirements document RFC 1123.
Saving space on stored dates persisted into the Unix era, with most systems representing dates to a single 32-bit word, typically representing dates as elapsed seconds from some fixed date
Unix time
Unix time, or POSIX time, is a system for describing instants in time, defined as the number of seconds elapsed since midnight Coordinated Universal Time of Thursday, January 1, 1970 , not counting leap seconds, which are declared by the International Earth Rotation and Reference Systems Service...
.
Resulting bugs from date programming
Storage of a combined date and time within a fixed binary field is often considered a solution, but the possibility for software to misinterpret dates remains because such date and time representations must be relative to some known origin. Rollover of such systems is still a problem but can happen at varying dates and can fail in various ways. For example:- The Microsoft ExcelMicrosoft ExcelMicrosoft Excel is a proprietary commercial spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables, and a macro programming language called Visual Basic for Applications...
spreadsheet program had a very elementary Y2K problem: Excel (in both Windows and Mac versions, when they are set to start at 1900) incorrectly set the year 1900 as a leap year for compatibility with Lotus 1-2-3. In addition, the years 2100, 2200, and so on, were regarded as leap years. This bug was fixed in later versions, but since the epochEpoch (reference date)In the fields of chronology and periodization, an epoch is an instance in time chosen as the origin of a particular era. The "epoch" then serves as a reference point from which time is measured...
of the Excel timestamp was set to the meaningless date ofJanuary 0, 1900in previous versions, the year 1900 is still regarded as a leap year to maintain backward compatibility. - In the C programming languageC (programming language)C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
, the standard library function to extract the year from a timestamp returns the year minus 1900. Many programs using functions from C, such as PerlPerlPerl is a high-level, general-purpose, interpreted, dynamic programming language. Perl was originally developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions and become widely popular...
and JavaJava (programming language)Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...
, two programming languages widely used in web development, incorrectly treated this value as the last two digits of the year. On the web this was usually a harmless presentation bug, but it did cause many dynamically generated web pages to display January 1, 2000 as "1/1/19100", "1/1/100", or other variants, depending on the display format. - JavaScriptJavaScriptJavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
was changed due to the concerns of the Y2K bug, and the return value for years changed and thus differed between versions from sometimes being a four digit representation and sometimes a two-digit representation forcing programmers to rewrite already working code to make sure web pages worked for all versions. This forced programmers to change already working code and add checks to see if the returned date was less than 1900 and react accordingly. - Older applications written for the commonly used UNIX Source Code Control SystemSource Code Control SystemSource Code Control System is an early revision control system, geared toward program source code and other text files. It was originally developed in SNOBOL at Bell Labs in 1972 by Marc J. Rochkind for an IBM System/370 computer running OS/360 MVT...
failed to handle years that began with the digit "2". - In the Windows 3.x file manager, dates displayed as 1/1/19:0 for 1/1/2000 (because the colon is the character after "9" in the ASCIIASCIIThe American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
character set). An update was available.
9 September 1999
Even before 1 January 2000 arrived, there were also some worries about 9 September 1999 (albeit lesser compared to those generated by Y2K). Because this date could also be written in the numeric format 9/9/99, it could have conflicted with the date value9999, frequently used to specify an unknown date. It was thus possible that database programs might act on the records containing unknown dates on that day. Somewhat similar to this is the end-of-file code 9999, used in older programming languages. While fears arose that some programs might unexpectedly terminate on that date, the bug was more likely to confuse computer operators than machines.Leap years
Mostly, a year is a leap year if it is evenly divisible by four. A year divisible by 100, however, is not a leap year on the Gregorian calendar unless it is also divisible by 400. For example, 1600 was a leap year, but 1700, 1800 and 1900 were not. Some programs may have relied on the oversimplified rule that a year divisible by four is a leap year. This method works fine for the year 2000 (because it is a leap year), and will not become a problem until 2100, when older legacy programs will likely have long since been replaced. Other programs contained incorrect leap year logic, assuming for instance that no year divisible by 100 could be a leap year. An assessment of this leap year problem including a number of real life code fragments appeared in 1998. For information on why century years are treated differently, see Gregorian calendarGregorian calendar
The Gregorian calendar, also known as the Western calendar, or Christian calendar, is the internationally accepted civil calendar. It was introduced by Pope Gregory XIII, after whom the calendar was named, by a decree signed on 24 February 1582, a papal bull known by its opening words Inter...
.
Year 2010 problem
Some systems had problems once the year rolled over to 2010. This was dubbed by some in the media as the "Y2K+10" or "Y2.01k" problem.The main source of problems was confusion between hexadecimal number encoding and Binary-coded decimal
Binary-coded decimal
In computing and electronic systems, binary-coded decimal is a digital encoding method for numbers using decimal notation, with each decimal digit represented by its own binary sequence. In BCD, a numeral is usually represented by four bits which, in general, represent the decimal range 0 through 9...
(BCD) encodings of numbers. Both hexadecimal and BCD encode the numbers 0–9 as 0x0–0x9. But BCD encodes the number 10 as 0x10, whereas hexadecimal encodes the number 10 as 0x0A; 0x10 interpreted as a hexadecimal encoding represents the number 16.
For example, because the SMS protocol uses BCD for dates, some mobile phone software incorrectly reported dates of SMSes as 2016 instead of 2010. Windows Mobile
Windows Mobile
Windows Mobile is a mobile operating system developed by Microsoft that was used in smartphones and Pocket PCs, but by 2011 was rarely supplied on new phones. The last version is "Windows Mobile 6.5.5"; it is superseded by Windows Phone, which does not run Windows Mobile software.Windows Mobile is...
is the first software reported to have been affected by this glitch; in some cases WM6 changes the date of any incoming SMS message sent after 1 January 2010 from the year "2010" to "2016". It has been said that this tends to affect phones on the CDMA network (not using SIM cards).
Other systems affected include EFTPOS
EFTPOS
EFTPOS is the general term used for debit card based systems used for processing transactions through terminals at points of sale. In Australia and New Zealand it is also the brand name of the specific system used for such payments...
terminals, and older Sony PlayStation 3 models (except the Slim).
The most important such glitch occurred in Germany, where upwards of 20 million bank cards became unusable, and with Citibank Belgium, whose digipass customer identification chips stopped working.
Year 2038 problem
The original Unix timestamp (time_t) stores a date and time as a signed 32-bit integer representing the number of seconds since January 1, 1970. During and after 2038, this number will exceed , the largest number representable by a signed 32-bit integer, causing the Year 2038 problemYear 2038 problem
The year 2038 problem may cause some computer software to fail at some point near the year 2038...
(also known as Unix Millennium bug, or Y2K38). To solve this problem, many systems and languages have switched to a 64-bit timestamp, or supplied alternatives which are 64-bit.
Programming solutions
Several very different approaches were used to solve the Year 2000 problem in legacy systems. Three of them follow:- Date expansion: Two-digit years were expanded to include the century (becoming four-digit years) in programs, files, and databases. This was considered the "purest" solution, resulting in unambiguous dates that are permanent and easy to maintain. However, this method was costly, requiring massive testing and conversion efforts, and usually affecting entire systems.
- Date re-partitioning: In legacy databases whose size could not be economically changed, six-digit year/month/day codes were converted to three-digit years (with 1999 represented as 099 and 2001 represented as 101, etc.) and three-digit days (ordinal dateOrdinal dateAn ordinal date is a calendar date typically consisting of a year and a day of year ranging between 1 and 366 , though year may sometimes be omitted...
in year). Only input and output instructions for the date fields had to be modified, but most other date operations, and whole record operations required no change. This delays the eventual roll-over problem to the end of the year 2899. - Windowing: Two-digit years were retained, and programs determined the century value only when needed for particular functions, such as date comparisons and calculations. (The century "window" refers to the 100-year period to which a date belongs.) This technique, which required installing small patches of code into programs, was simpler to test and implement than date expansion, thus much less costly. While not a permanent solution, windowing fixes were usually designed to work for several decades. This was thought acceptable, as older legacy systems tend to eventually get replaced by newer technology.
Before 2000
- On 28 December 1999, 10,000 card swipe machines issued by HSBCHSBCHSBC Holdings plc is a global banking and financial services company headquartered in Canary Wharf, London, United Kingdom. it is the world's second-largest banking and financial services group and second-largest public company according to a composite measure by Forbes magazine...
and manufactured by RacalRacalRacal Electronics plc was once the third-largest British electronics firm. Listed on the London Stock Exchange and once a constituent of the FTSE 100 Index, Racal was a diversified company, offering products including: as voice and data recorders; point of sale terminals; laboratory instruments;...
stopped processing credit and debit card transactions. The stores relied on paper transactions until the machines started working again on 1 January.
On 1 January 2000
When 1 January 2000 arrived, there were problems generally regarded as minor. Problems did not always have to occur precisely at midnight. Some programs were not active at that moment and would only show up when they were invoked. Not all problems recorded were directly linked to Y2K programming in a causalityCausality
Causality is the relationship between an event and a second event , where the second event is understood as a consequence of the first....
; minor technological glitches occur on a regular basis. Some caused erroneous results, some caused machines to stop working, some caused date errors, and two caused malfunctions.
Reported problems include:
- In SheffieldSheffieldSheffield is a city and metropolitan borough of South Yorkshire, England. Its name derives from the River Sheaf, which runs through the city. Historically a part of the West Riding of Yorkshire, and with some of its southern suburbs annexed from Derbyshire, the city has grown from its largely...
, United KingdomUnited KingdomThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, incorrect Down's syndrome test results were sent to 154 pregnant women and two abortions were carried out as a direct result of a Y2K bug. Four Down's syndrome babies were also born to mothers who had been told they were in the low-risk group. - In IshikawaIshikawa-Places:*Ishikawa Prefecture*Ishikawa-gun, district, Ishikawa Prefecture*Ishikawa-gun, district, Fukushima Prefecture*Ishikawa-machi, town, Fukushima Prefecture*Ishikawa-shi, city, Okinawa Prefecture-Real people:*Alexandre Ishikawa, Brazilian director...
, JapanJapanJapan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, radiation-monitoring equipment failed at midnight; however, officials stated there was no risk to the public. - In Onagawa, Japan, an alarm sounded at a nuclear power plant at two minutes after midnight.
- In Japan, at two minutes past midnight, Osaka Media Port, a telecommunications carrier, found errors in the date management part of the company's network. The problem was fixed by 02:43 and no services were disrupted.
- In Japan, NTT Mobile Communications Network (NTT DoCoMoNTT DoCoMois the predominant mobile phone operator in Japan. The name is officially an abbreviation of the phrase, "do communications over the mobile network", and is also from a compound word dokomo, meaning "everywhere" in Japanese. Docomo provides phone, video phone , i-mode , and mail services...
), Japan's largest cellular operator, reported on 1 January 2000, that some models of mobile telephones were deleting new messages received, rather than the older messages, as the memory filled up. - In AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, bus-ticket-validation machines in two states failed to operate. - In the United StatesUnited StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, 150 slot machinesDelaware LotteryThe Delaware Lottery is run by the government of Delaware. Unlike most US lotteries, Delaware offers video lottery; its other games include Mega Millions, Powerball, Cash 5, Play 3, and Play 4....
at race tracks in DelawareDelawareDelaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...
stopped working. - In the United States, the U.S. Naval Observatory, which runs the master clock that keeps the country's official time, gave the date on its website as Jan. 1, 19100.
- In FranceFranceThe French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, the national weather forecasting service, Meteo France, said a Y2K bug made the date on a webpage show a map with Saturday's weather forecast as "01/01/19100". This also occurred on other websites, including att.net, at the time a general-purpose portal site primarily for AT&T WorldnetAT&T WorldNetatt.net is a web portal and Internet service provider from AT&T, Inc..- AT&T :ATT.NET is a consumer web portal provided by AT&T, Inc...
customers in the United States.
United States
The United States Government responded to the Y2K threat by passing the Year 2000 Information and Readiness Disclosure Act, by working with private sector counterparts in order to ensure readiness, and by creating internal continuity of operations plans in the event of problems. The effort was coordinated out of the White House by the President's Council on Year 2000 Conversion, headed by John KoskinenJohn Koskinen
John Koskinen served as Non-Executive Chairman of Freddie Mac since September, 2008. He served as President of the U.S. Soccer Foundation from 2004-2008. He previously served as the Deputy Mayor of the District of Columbia, the Deputy Director for Management of the Office of Management and Budget,...
. The White House
White House
The White House is the official residence and principal workplace of the president of the United States. Located at 1600 Pennsylvania Avenue NW in Washington, D.C., the house was designed by Irish-born James Hoban, and built between 1792 and 1800 of white-painted Aquia sandstone in the Neoclassical...
effort was conducted in coordination with the then-independent Federal Emergency Management Agency
Federal Emergency Management Agency
The Federal Emergency Management Agency is an agency of the United States Department of Homeland Security, initially created by Presidential Reorganization Plan No. 1 of 1978 and implemented by two Executive Orders...
(FEMA), and an interim Critical Infrastructure Protection Group, then in the Department of Justice, now in Homeland Security. The Dutch Government promoted Y2K Information Sharing and Analysis Centers (ISACs) to share readiness between industries, without threat of antitrust violations or liability based on information shared.
The U.S. Government followed a three part approach to the problem: (1) Outreach and Advocacy (2) Monitoring and Assessment and (3) Contingency Planning and Regulation.
A feature of U.S. Government outreach was Y2K websites including Y2K.GOV. Presently, many U.S. Government agencies have taken down their Y2K websites. Some of these documents may be available through National Archives and Records Administration
National Archives and Records Administration
The National Archives and Records Administration is an independent agency of the United States government charged with preserving and documenting government and historical records and with increasing public access to those documents, which comprise the National Archives...
or the Wayback Machine
Wayback Machine
The Wayback Machine is a digital time capsule created by the Internet Archive non-profit organization, based in San Francisco, California. It is maintained with content from Alexa Internet. The service enables users to see archived versions of web pages across time, which the Archive calls a "three...
.
Each federal agency had its own Y2K task force which worked with its private sector counter parts. The FCC had the FCC Year 2000 Task Force.
Most industries had contingency plans that relied upon the Internet for backup communications. However, as no federal agency had clear authority with regard to the Internet at this time (it had passed from the U.S. Department of Defense to the U.S. National Science Foundation and then to the U.S. Department of Commerce), no agency was assessing the readiness of the Internet itself. Therefore on July 30, 1999 the White House held the White House Internet Y2K Roundtable.
Norway and Finland
Norway and Finland changed their National identification numberNational identification number
A national identification number, national identity number, or national insurance number is used by the governments of many countries as a means of tracking their citizens, permanent residents, and temporary residents for the purposes of work, taxation, government benefits, health care, and other...
, to indicate the century in which a person was born. In both countries the birth year was indicated with two digits only. However, a similar problem already existed, the "Year 1900 problem
Year 1900 problem
The year 1900 problem concerns the misinterpretation of years recorded by only their last two digits, and whether they occurred before or after the year 1900...
", about distinguishing between people born in the 20th or 19th century, so the timing was more because of the Y2K attention than a solution to a new problem. In Finland the problem was solved by replacing the hyphen ("
Bulgaria
Although only two digits are allocated for the birth year in the Bulgarian national identification numberUniform civil number
The uniform civil number is a 10-digit unique number assigned to each Bulgarian citizen or resident foreign national. It serves as a national identification number. An EGN is assigned to Bulgarians at birth, or when a birth certificate is issued...
, the year 1900 problem
Year 1900 problem
The year 1900 problem concerns the misinterpretation of years recorded by only their last two digits, and whether they occurred before or after the year 1900...
and subsequently the Y2K problem were addressed by the use of unused values above 12 in the month range. For all persons born before 1900, the month is stored as calendar month + 20, and for all persons born after 1999, the month is stored as calendar month + 40.
International cooperation
The International Y2K Cooperation Center (IY2KCC) was established at the behest of national Y2K coordinators from over 120 countries when they met at the First Global Meeting of National Y2K Coordinators at the United Nations in December 1988. IY2KCC established an office in Washington, D.C. in March 1999. Funding was provided by the World Bank, and Bruce W. McConnell was appointed as director.IY2KCC's mission was to "promote increased strategic cooperation and action among governments, peoples, and the private sector to minimize adverse Y2K effects on the global society and economy." Activities of IY2KCC were conducted in six areas:
- National Readiness: Promoting Y2K programs worldwide
- Regional Cooperation: Promoting and supporting coordination within defined geographic areas
- Sector Cooperation: Promoting and supporting coordination within and across defined economic sectors
- Continuity and Response Cooperation: Promoting and supporting coordination to ensure essential services and provisions for emergency response
- Information Cooperation: Promoting and supporting international information sharing and publicity
- Facilitation and Assistance: Organizing global meetings of Y2K coordinators and to identify resources
IY2KCC closed down in March 2000.
Private sector response
- The United States established the Year 2000 Information and Readiness Disclosure Act, which limited the liability of businesses who had properly disclosed their Y2K readiness.
- Insurance companies sold insurance policies covering failure of businesses due to Y2K problems.
- Attorneys organized and mobilized for Y2K class action lawsuits (which were not pursued).
- Survivalist-related businesses (gun dealers, surplus and sporting goods, Latter Day Saints (Mormon) bookstores selling freeze-dried food) anticipated increased business in the final months of 1999 in an event known as the Y2K scare. Some of these businesses experienced increased sales; some did not.
- The Long Now FoundationLong Now FoundationThe Long Now Foundation, established in 1996, is a private organization that seeks to become the seed of a very long-term cultural institution. It aims to provide a counterpoint to what it views as today's "faster/cheaper" mindset and to promote "slower/better" thinking...
, which (in their words) "seeks to promote 'slower/better' thinking and to foster creativity in the framework of the next 10,000 years", has a policy of anticipating the Year 10,000 problemYear 10,000 problemThe Year 10,000 problem is the class of all potential software bugs that would emerge when the need to express years with five digits arises...
by writing all years with five digits. For example, they list "01996" as their year of founding. - While there was no one comprehensive Internet Y2K effort, multiple Internet trade associations and organizations banded together to form the Internet Year 2000 Campaign. This effort partnered with the White House's Internet Y2K Roundtable.
The Y2K issue was a major topic of discussion in the late 1990s and, predictably, showed up in most popular media. A number of "Y2K disaster" books were published such as Deadline Y2K by Mark Joseph. Movies such as Y2K: Year to Kill capitalized on the currency of Y2K, as did numerous TV shows, comic strips, and computer games.
Cost
The total cost of the work done in preparation for Y2K is estimated at over 300 billion US dollars. IDC calculated that the U.S. spent an estimated $134 billion preparing for Y2K, and another $13 billion fixing problems in 2000 and 2001. Worldwide, $308 billion was estimated to have been spent on Y2K remediation. There are two ways to view the events of 2000 from the perspective of its aftermath:Supporting view
This view holds that the vast majority of problems had been fixed correctly, and the money was well spent. The situation was essentially one of preemptive alarm. Those who hold this view claim that the lack of problems at the date change reflect the completeness of the project, and that many computer applications would not have continued to function into the 21st century without correction or remediation.- It has also been suggested that on September 11, 2001, the New York infrastructure (including subways, phone service, and financial transactions) were able to continue operation because of the redundant networks established in the event of Y2K bug impact and the contingency plans devised by companies. The terrorist attacks and the following prolonged blackout to lower Manhattan had minimal effect on global banking systems. Backup systems were activated at various locations around the region, many of which had been established to deal with a possible complete failure of networks in the financial district on December 31, 1999.
- Expected problems that were not seen by small businesses and small organizations were in fact prevented by Y2K fixes embedded in routine updates to operating system and utility software that were applied several years before 31 December 1999.
- It was suggested that Y2K plans were used to ground aircraft on 9/11, but the grounding was a variant of the SCATANA procedures developed in 1958.
Opposing view
Others have claimed that there were no, or very few, critical problems to begin with, and that correcting the few minor mistakes as they occurred, the fix on failure approach, would have been the most efficient and cost effective way to solve the problem. Editorial writing in the Wall Street JournalThe Wall Street Journal
The Wall Street Journal is an American English-language international daily newspaper. It is published in New York City by Dow Jones & Company, a division of News Corporation, along with the Asian and European editions of the Journal....
called Y2K an "end-of-the-world cult" and the "hoax of the century". The opposing view was bolstered by a number of observations.
- The lack of Y2K-related problems in schools, many of which undertook little or no remediation effort. By September 1, 1999, only 28% of U.S. schools had achieved compliance for mission critical systems, and a government report predicted that "Y2K failures could very well plague the computers used by schools to manage payrolls, student records, online curricula, and building safety systems".
- The lack of Y2K-related problems in an estimated 1.5 million small businesses that undertook no remediation effort. On 3 January 2000 (the first weekday of the year), the Small Business Administration received an estimated 40 calls from businesses with computer problems, similar to the average. None of the problems were critical.
- The lack of Y2K-related problems in countries such as ItalyItalyItaly , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, which undertook a far more limited remediation effort than the United States. In an October 22, 1999, report, a US Senate Committee expressed concern about safe travel outside of the United States. The report stated that overseas public transit systems were considered vulnerable because many did not have an aggressive response plan in place for any problems. Internationally, the report singled out ItalyItalyItaly , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, ChinaChinaChinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and RussiaRussiaRussia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
as poorly prepared. The Australian government evacuated all but three embassy staff from Russia. None of these countries experienced any Y2K problems regarded as worth reporting. - The absence of Y2K-related problems occurring before January 1, 2000, even though the 2000 financial year commenced in 1999 in many jurisdictions, and a wide range of forward-looking calculations involved dates in 2000 and later years. Estimates undertaken in the leadup to 2000 suggested that around 25% of all problems should have occurred before 2000. Critics of large-scale remediation argued, during 1999, that the absence of significant problems, even in systems that had not been rendered compliant, suggested that the scale of the problem had been severely overestimated.
See also
- IPv4 address exhaustion, problems caused by the limited allocation size for numeric Internet addresses
- ISO 8601ISO 8601ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times is an international standard covering the exchange of date and time-related data. It was issued by the International Organization for Standardization and was first published in 1988...
, an international standard for representing dates and times, which mandates the use of (at least) four digits for the year - Problems with epoch-based computer time representation
- Perpetual calendarPerpetual calendarA perpetual calendar is a calendar which is good for a span of many years, such as the Runic calendar.- General information :...
, a calendar valid for many years, including before and after 2000 - Y2K – World in CrisisY2K – World in CrisisY2K – A World in Crisis is a 1999 documentary television series produced by Studio W and Warren Chaney Productions for network and cable broadcast. The series was written and directed by Warren Chaney and starred Hugh O'Brian, Dick Van Patten, Richard Anderson, Richard Roundtree and Deborah...
External links
- Center for Y2K and Society Records, Charles Babbage InstituteCharles Babbage InstituteThe Charles Babbage Institute is a research center at the University of Minnesota specializing in the history of information technology, particularly the history since 1935 of digital computing, programming/software, and computer networking....
, University of Minnesota. Documents activities of Center for Y2K and Society (based in Washington DC) working with non-profit institutions and foundations to respond to possible societal impacts of the Y2K computer problem: helping the poor and vulnerable as well as protecting human health and the environment. Records donated by executive director, Norman L. Dean. - International Y2K Cooperation Center Records, 1998-2000, Charles Babbage InstituteCharles Babbage InstituteThe Charles Babbage Institute is a research center at the University of Minnesota specializing in the history of information technology, particularly the history since 1935 of digital computing, programming/software, and computer networking....
, University of Minnesota. Collection contains the materials of the International Y2K Cooperation Center. Includes country reports, news clippings, country questionnaires, country telephone directories, background materials, audio visual materials and papers of Bruce W. McConnell, director of IY2KCC. - Preparing for an Apocalypse: Y2K, Charles Babbage InstituteCharles Babbage InstituteThe Charles Babbage Institute is a research center at the University of Minnesota specializing in the history of information technology, particularly the history since 1935 of digital computing, programming/software, and computer networking....
, University of Minnesota. A web exhibit curated by Stephanie H. Crowe - BBC: Y2K coverage
- In The Beginning There Was The Nerd — BBC Radio documentary about the history of computers and the millennium bug 10 years after using archival recordings.
- The Surprising Legacy Of Y2K — Radio documentary by American Public Media, on the history and legacy of the millennium bug five years on.
- The Yawn of a New Millennium
- CBC Digital Archives - The Eve of the Millennium
- Time running out for PCs at big companies CNNCNNCable News Network is a U.S. cable news channel founded in 1980 by Ted Turner. Upon its launch, CNN was the first channel to provide 24-hour television news coverage, and the first all-news television channel in the United States...