N.Y. Real Prop. Tax Law § 808

§ 808. Correction of clerical errors in county equalizations. If it\nappears to the board of supervisors of any county that a clerical error\nhas been made by the county equalization agency and that by reason of\nsuch error injustice has been done to one or more cities or towns and\nthat two years have not elapsed since the equalization, the error may be\ncorrected by the board of supervisors. If the equalization cannot be\ncorrected before taxes are levied on the basis thereof, such board shall\ndetermine the amount of county taxes paid or payable by any such city or\ntown under such equalization in excess of or less than that which such\ncity or town would have paid under such equalization as corrected. The\nexcess shall be subtracted, or the deficiency shall be added, from or to\nthe next county tax levy in such city or town as the situation may\nrequire.\n