An Act amending the act of March 16, 1970 (P. L. 180, No. 69), entitled "An act relating to State taxation; changing the manner in which tentative and annual taxes are to be paid; providing a penalty in certain cases; and making a repealer," further providing for a revision in the method of reporting, for additional tax and interest, for the underpayment of annual and quarterly taxes, for removing additional tax for understatement, and for the quarterly reporting and payment of the tentative corporate net income tax and corporation income tax.