N.Y. Gen. Constr. Law § 57

§ 57. Year, common and leap. For the purpose of computing and\nreckoning the days of the year in the same regular course in the future,\nevery year, the number of which in the Christian era is a multiple of\nfour, is a bissextile or leap year consisting of three hundred and\nsixty-six days, unless such number of the year is a multiple of one\nhundred and the first two figures thereof treated as a separate number\nis not a multiple of four, and every year which is not a leap year is a\ncommon year consisting of three hundred and sixty-five days.\n