Time Formatting and Storage Bugs - Two-digit Year Representations

Two-digit Year Representations

Main article: Year 2000 problem See also: Year 1900 problem

Follow-on problems caused by certain temporary fixes to the Y2K problem will crop up at various points in the 21st century. Some programs were made Y2K-compliant by continuing to use two digit years, but picking an arbitrary year prior to which those years are interpreted as 20xx, and after which are interpreted as 19xx.

For example, a program may have been changed so that it treats two-digit year values 00–68 as referring to 2000 through 2068, and values 69–99 as referring to 1969 through 1999. Such a program will not be able to correctly deal with years beyond 2068.

For applications required to calculate the birth year (or other passed year), such an algorithm has long been used to overcome the Year 1900 problem, but it has failed to recognise people over 100 years old.