N.Y. Retire. & Soc. Sec. Law § 424

§ 424. Distribution of earnings. At the close of each fiscal year,\nthe average rate of investment earnings of the common retirement fund\nshall be computed by the actuary and certified to the comptroller. This\nrate shall be determined from the investment earnings during the\ncalendar year, which ended three months prior to the close of the fiscal\nyear. The amount of such earnings attributable to each retirement system\nshall be computed by the actuary and certified to the comptroller, who\nshall thereupon credit each retirement system in accordance therewith.\n