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This command is outdated, no pun intended. It treats the output differently in different browsers and may give a 2, 3 or 4 year answer. IE generally accepts a 4 character year from IE4 and up but others may accept a 2 year date for years between 1900 and 1999, allowing you to add 1900 plus the 2 digit number. Some browsers accept a 3 digit number for years 2000 and up, allowing you to add 1900 plus the number. We suggest the use of setFullYear.