New York Codes, Rules and Regulations
Title 21 - Miscellaneous
Chapter LVIII - New York State Teachers' Retirement System
Part 5002 - Credit For Prior/previous Service
Section 5002.3 - Payment for previous service for members with a date of membership on or after July 27, 1976, but before September 1, 1983, who are eligible to purchase such service

(a) The amount of money to be paid for previous service which was originally credited under a membership dated prior to July 27, 1976 (Tier I or II) shall be three percent of wages earned for such service.

(b) The amount of money to be paid for previous service which was originally credited under a former membership dated on or after July 27, 1976 but before September 1, 1983 (Tier III), shall be three percent of wages earned for such service, together with interest from the date of such service through the date of repayment at the rate of five percent per annum compounded annually.

(c) The amount of money to be paid for previous service which was not previously credited in a public retirement system in New York State which predates the entry in the retirement system, pursuant to paragraphs (i) and (ii) of subdivision b of section 513 of the Retirement and Social Security Law, shall be three percent of wages earned for such service.