Working With Cross-Century Dates

Many existing business applications use two digits to designate a year, instead of four digits. When they receive a value for a year, such as 00, they typically interpret it as 1900, assuming that the first two digits are 19, for the twentieth century. These applications require a way to handle dates when the century changes (for example, from the twentieth to the twenty-first), or when they need to perform comparisons or arithmetic on dates that span more than one century.

The cross-century date feature described in this topic enables the correct interpretation of the century if it is not explicitly provided, or is assumed to be the twentieth. The feature is application-based, that is, it involves modifications to procedures or metadata so that dates are accurately interpreted and processed. The feature is called the sliding window technique.