Section 2840. A. Each county assessor shall prepare, build, and maintain permanent records containing the following information:

1. The classification, grade, and value of each tract of land located outside cities and towns and platted subdivisions and additions and the improvements thereon;

2. The description and value of all lots and tracts and the improvements thereon, and a list of lands that have been annexed to any city or town, commencing with the lowest numbered section and the different subdivisions and fractional parts thereof in the lowest numbered townships in the lowest numbered range in the county, and ending with the highest numbered section, township, and range and the improvements thereon; and

3. The information required herein to be shown on such permanent records shall be shown as to tax exempt as well as taxable property, and shall be in such forms as may be acceptable to the Oklahoma Tax Commission. It shall not be necessary to place upon such records any grade or value on land and improvements owned by the United States of America, the State of Oklahoma this state or any subdivision thereof, or any land and improvements exempt from ad valorem taxation by reason of the same being used exclusively and directly for religious, charitable, or educational purposes, such as churches, schools, colleges, universities, cemeteries, and all lands owned by railroads, air carriers, and public service corporations that are assessed by the State Board of Equalization. Exempt Indian land and other exempt property shall be valued and the value placed upon such records.

B. When the valuation of the real estate of each county has been completed, as required by this section, it shall be the mandatory duty of the county assessor and each of his or her successors in office, to continuously maintain, revise, and correct the records relating thereto, and to continuously adjust and correct assessed valuations in conformity therewith. Such maintenance, revision, and correction shall be made each year based upon the results of the calculations required by law to be performed each year in order to determine the fair cash value of all property within the county.

C. Each county assessor shall request in his or her budget request each year sufficient funds to carry out the provisions of this section. It shall be the mandatory duty of the several boards of county commissioners, the several county excise boards, and the several county budget boards each year to make sufficient appropriations to enable the county assessor to perform the duties required of him or her by this section. If any board of county commissioners, county excise board, or county budget board fails, neglects, or refuses, upon written request of the county assessor, to provide adequate appropriations for supplies, deputy hire, or traveling expenses for the performance of the duties imposed upon the county assessor by this section, such appropriations may be obtained by mandamus action instituted in district court by the county assessor or any other county officer, or any taxpayer of the county.

D. The classification and valuation provided for by this section shall be done under the supervisory assistance of the Oklahoma Tax Commission. The forms used in such classification and valuation of property shall be prescribed by the Oklahoma Tax Commission. Where the classification and valuation has already been completed, it shall not be necessary for the county assessor to again make such classification and valuation, except it shall be the duty of such county assessor to continuously maintain, revise, and correct the same as required by this section.