Patent US 6,236,992

An improved computing system is described which eliminates potential errors associated with Year 2000 malfunctions. This system may be a retrofitted version of an existing computer system which has been intentionally date regressed to function in a time zone that eliminates potential date computation problems. To effectuate a complete regression of such system, existing databases are date regressed, existing programs are time synchronized with such databases, and existing I/O routines are modified to assure date arithmetic integrity. To handle years outside of a 100 year span, chronological encapsulation is used to set up year specific databases which interact with associated time synchronized copies of any main programs on such system. Multiple regressed states can be implemented in such system by a series of one or more regressed databases and associated synchronized programs, so that date computations can be handled for date data fields spanning across two or three centuries worth of data using only two digit decimal field formats for records.