1. In addition to the revenue limit imposed by § 18 of this Article, the general assembly in any fiscal year shall not increase taxes or fees without voter approval that in total produce new annual revenues greater than either fifty million dollars adjusted annually by the percentage change in the personal income of Missouri for the second previous fiscal year, or one percent of total state revenues for the second fiscal year prior to the general assembly’s action, whichever is less. In the event that an individual or series of tax or fee increases exceed the ceiling established in this subsection, the taxes or fees shall be submitted by the general assembly to a public vote starting with the largest increase in the given year, and including all increases in descending order, until the aggregate of the remaining increases and decreases is less than the ceiling provided in this subsection.

2. The term “new annual revenues” means the net increase in annual revenues produced by the total of all tax or fee increases enacted by the general assembly in a fiscal year, less applicable refunds and less all contemporaneously occurring tax or fee reductions in that same fiscal year, and shall not include interest earnings on the proceeds of the tax or fee increase. For purposes of this calculation, “enacted by the general assembly” shall include any and all bills that are truly agreed to and finally passed within that fiscal year, except bills vetoed by the governor and not overridden by the general assembly. Each individual tax or fee increase shall be measured by the estimated new annual revenues collected during the first fiscal year that it is fully effective. The term “increase taxes or fees” means any law or laws passed by the general assembly after the effective date of this section^* that increase the rate of an existing tax or fee, impose a new tax or fee, or broaden the scope of a tax or fee to include additional class of property, activity, or income, but shall not include the extension of an existing tax or fee which was set to expire.

3. In the event of an emergency, the general assembly may increase taxes, licenses or fees for one year beyond the limit in this subsection under the same procedure specified in § 19 of this Article.

4. Compliance with the limit in this section shall be measured by calculating the aggregate actual new annual revenues produced in the first fiscal year that each individual tax or fee change is fully effective.

5. Any taxpayer or statewide elected official may bring an action under the provisions of § 23 of this Article to enforce compliance with the provisions of this section. The Missouri supreme court shall have original jurisdiction to hear any challenge brought by any statewide elected official to enforce this section. In such enforcement actions, the court shall invalidate the taxes and fees which should have received a public vote as defined in subsection 1 of this section. The court shall order remedies of the amount of revenue collected in excess of the limit in this subsection as the court finds appropriate in order to allow such excess amounts to be refunded or to reduce taxes and/or fees in the future to offset the excess monies collected.