An Act amending the act of May 7, 1965 (P. L. 48, No. 38), entitled "A supplement to the act of May 28, 1915 (P. L. 596, No. 259), entitled 'An act requiring cities of the second class to establish a pension fund for employes of said cities, and regulating the administration and the payment of such pensions,' as to employes of second class A cities, ***," further providing for the rate of employe contributions.