N.Y. Real Property Tax Law § 1904
2. The assessors in each approved assessing unit which has adopted the provisions of this section shall, in the first year in which revaluation assessments are to be entered on the assessment roll and for each of the next three succeeding years, determine for each parcel for which the revaluation assessment is greater than the assessment for the same parcel on the immediately preceding assessment roll, a transition assessment as follows:
3. The assessors in each approved assessing unit which has adopted the provisions of this section shall, in the first year in which revaluation assessments are to be entered on the assessment roll and for each of the next three succeeding years, determine for each parcel for which the revaluation assessment is less than the assessment for the same parcel on the immediately preceding assessment roll, a transition assessment as follows: