In addition to the salary or compensation provided elsewhere in this article, the county commission of each county shall pay to the assessor, on an annual basis, on and after July 1, 1977, additional compensation in accordance with the provisions of this section and section six-b of this article for such additional duties required of him by this section.
To receive such additional compensation, the following duties are hereby imposed upon every assessor of this state:
(1) He shall annually complete a sales ratio analysis in a manner prescribed by the State Tax Commissioner.