A municipality which adopts this Division 18 may levy, annually, a tax of not more than .0075% of the value, as equalized or assessed by the Department of Revenue, of all taxable property therein, for the current year, to provide revenue for the salaries of and expenses incident to the performance of the duties of the community nurses. This tax shall be in addition to all taxes authorized by law to be levied and collected in that municipality and shall be in addition to the taxes authorized to be levied for general purposes under Section 8-3-1.
     The foregoing limitation upon tax rate may be increased or decreased according to the referendum provisions of the General Revenue Law of Illinois.