F.4 Your Retirement Benefit Your Benefit Service and Average Contribution Rate determine your monthly retirement benefit. Your Average Contribution Rate for benefits earned prior to July 1, 1990 is determined by the employer Contributions made on your behalf divided by your hours worked. Only Contributions and hours worked after July 1, 1971, are counted. In addition, only Contributions up to $2.00 per hour are used. Average Contribution Rate (ACR) $1.00 per Hour or Less Benefit Service X ACR times $27.90 = Monthly Retirement Benefit Average Contribution Rate Over $1.00 but Less Than $2.00 per Hour Benefit Service X $27.90 plus $23.50 times (ACR - $1) = Monthly Retirement Benefit Average Contribution Rate Equals or Exceeds $2.00 per Hour Benefit Service X $51.40 = Monthly Retirement Benefit Your Monthly Retirement Benefit under this Appendix F is calculated as a five year Certain Life Annuity. If you receive another form of payment, your monthly benefit is actuarially adjusted for that form of payment. If you postpone your retirement beyond your Normal Retirement Age, you will receive an increase in your benefits to reflect the delay in the commencement of benefits.