Tennessee Code Title 4. State Government § 4-3-710

(a) Notwithstanding the right or ability of a county or municipality to take a special census during the interim between the regular decennial federal census, the department of economic and community development shall revise and certify the population of each county and municipality, and the aggregate population of the state, prior to July 1 each year during the interim between the regular decennial federal census according to this section for purposes of ensuring equitable population-based allocation and distribution of moneys to counties and municipalities.

(b) The Boyd Center for Business and Economic Research at the University of Tennessee, through the Tennessee state data center, shall generate annual population estimates for each county and municipality and provide the estimates to the department of economic and community development for review and certification.

(c) Prior to July 1, the department of economic and community development shall provide the revised, certified populations of each county and municipality to the department of revenue and the department of finance and administration.  The allocation and distribution of moneys to counties and municipalities must be made according to the revised populations certified under this section, except in instances where a jurisdiction's population is revised as a result of a special census or in a year in which populations are revised as a result of the regular decennial federal census.