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Century Dates

The century cut-off date is used to determine the century for 2-digit years. This date defaults to 50, but you can change it using this INI option:

< Control >

DateFMT2To4Year =

Anything less than or equal to the cut-off year is considered to fall in the current century. For instance using the default of 50, 13 would be interpreted as 2013. Anything greater than the cut-off year is considered to fall in the previous century. For instance, again using the default of 50, 88 would be interpreted as 1988. This is important when you have to determine the years or days between two dates.

There is a scenario where the system overrides a 2-digit year output. This only happens when the input has 4-digits and the output has 2-digits and the resulting 2-digit output does not yield the same results when read in again.

For instance, suppose your input is 01/01/1927 and the cutoff year is 50. Normally any 2-digit year with a value less than 50 is considered part of the current century. So if the system outputs the data as 01/01/27 and then tries to read this date back in, you would get 01/01/2025 and not 01/01/1927.

The system changes its normal behavior because it is designed to be able to read its own output and come up with the result originally provided in the original input. If, however, you specifically tell the system you only want two digits, you will get that output, but the system may not be able to read it back in and get the same results.