December 31

December 31 is the 365th day of the year (366th in leap years) in the Gregorian calendar. This date is slightly more likely to fall on a Monday, Thursday or Saturday (58 in 400 years each) than on Tuesday or Wednesday (57), and slightly less likely to occur on a Friday or Sunday (56). It is widely known as New Year's Eve since the following day is New Year's Day. It is the last day of the year. The following day is January 1 of the following year.

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