To eliminate the need for the legislature to set the maximum and the minimum rates recoverable under workmen's compensation law by allowing the remuneration to be based upon sixty-six and two-thirds percent (66-2/3%) of the injured employee's average weekly wage, not to exceed sixty-six and two-thirds percent (66-2/3%) nor to be less than fifteen percent (15%) of the average weekly earnings for non-supervisory production employees in manufacturing and mining as determined by the Texas Employment Commission and published in its report, "The Average Weekly Earnings in Texas" for December 1972, and each even numbered year thereafter; this method for determining weekly compensation rates will apply to all employees sustaining a compensable injury on or after July 1, 1973; providing that this Act shall not affect any rights which have vested or accrued prior to the effective date hereof, and retaining prior laws in effect, insofar as injuries sustained prior to the effective date hereof; providing for a savings clause; repealing all laws in conflict; and declaring an emergency.