(1)    If a school board wishes to increase the total base wages of its employees in an amount that exceeds the limit under s. 111.70 (4) (mb) 2., the school board shall adopt a resolution to that effect. The resolution shall specify the amount by which the proposed total base wages increase will exceed the limit under s. 111.70 (4) (mb) 2. The resolution may not take effect unless it is approved in a referendum called for that purpose. The referendum shall occur in April for collective bargaining agreements that begin in July of that year. The results of a referendum apply to the total base wages only in the next collective bargaining agreement.

   (2)   The question submitted in the referendum shall be substantially as follows: “Shall the employees in the …. [school district] receive a total increase on wages from $….[current total base wages] to $….[proposed total base wages], which is a percentage wage increase that is …. [x] percent higher than the percent of the consumer price index increase, for a total percentage increase in wages of …. [x]?”