Conn. Gen. Stat. § 7-443: Initial rates of contribution by municipality.

The Retirement Commission shall fix the initial rates of contribution by municipalities on account of future pensions based on services rendered prior and subsequent to the acceptance of this part on an actuarial study of the municipalities whose acceptance is necessary to the taking effect of this part. It shall make a complete actuarial study of the experience of the retirement system established by this part at intervals of not more than five years and shall thereupon readjust the contributions to be made by municipalities.