; and (B) the total population of all counties. (4) Data For purposes of this subsection, the population of counties shall be determined based on the most recent year for which data are available from the Bureau of the Census and shall include all incorporated and unincorporated populations within the county. (d) Use of funds A county shall use the funds provided under a payment made under this section— (1) to cover only those costs of the county that— (A) are necessary expenditures incurred due to the public health emergency with respect to the Coronavirus Disease 2019 (COVID-19); (B) were not accounted for in the budget most recently approved as of February 29, 2020; and (C) were incurred during the period that begins on March 1, 2020, and ends on December 30, 2020; and (2) to compensate for any direct loss of revenue to the county as a result of such public health emergency. (e) Certification In order to receive a payment under this section, a county shall provide the Secretary with a certification signed by the Chief Executive for the county that the county’s proposed uses of the funds are consistent with subsection (d). (f) Inspector general oversight