Changes to the 1940 – 2039 date range for date formats with a 2-digit year

The current default date range for converting or verifying 2-digit year date formats is January 1, 1940 to December 31, 2039. For example, when using a date with only 2 digits to specify the year (for example,

*MDY, *DMY, or *YMD), years in the range of 40 to 99 are assumed to be 1940-1999 and years 00 to 39 are assumed to be 2000 to 2039.

Beginning in IBM i 7.5, an environment variable, QIBM_QBASEYEAR, can be used to set the base year to 1970 or 1940. When the base year is set to 1970, the implicit date range will be January 1, 1970 – December 31, 2069. When the base year is set to 1940, the implicit date range will be the same as the current default range of January 1, 1940 to December 31, 2039.

The default base year will change to 1970 in a future release. The QIBM_QBASEYEAR environment variable support is being made available now so that you can begin preparing for this change. See QIBM_QBASEYEAR environment variable to learn more about which functions are affected by the environment variable and how to set up the environment to test your applications with the 1970 base year. Applications that still use 2-digit date formats may need to change to use a date format that includes the century.