1. For county purposes the annual tax on property, not including taxes for the payment of valid bonded indebtedness or renewal bonds issued in lieu thereof, shall not exceed the rates herein specified: In counties having three hundred million dollars or more assessed valuation and having by operation of law attained the classification of a county of the first class, the rates shall not exceed thirty-five cents on the hundred dollars assessed valuation; and in all other counties, the rate shall not exceed fifty cents, except that in any county the maximum rates of taxation as limited in this section may be increased for not to exceed four years, when the rate and purpose of the increase are submitted to a vote and two-thirds of the voters of the county voting thereon shall vote therefor.

2. County commissions are hereby authorized to submit the question of increasing maximum tax rates herein specified, and shall submit the question when petitioned therefor by not less than ten percent of the voters of the county as determined by the total vote cast for governor in the last preceding general election for governor.

3. The question shall be submitted in substantially the following form:

Shall there be a levy for county purposes of ______ on the hundred dollars assessed valuation?

4. For any county, which by operation of law attains the classification of a county of the first class on or after January 1, 1991, which has a tax rate ceiling at or below thirty-five cents by application of section 137.073 or 137.115, whichever is applicable, it shall not be necessary to further reduce such county’s tax rate due to the attainment of such first class county status.