; and (ii) a number that is equal to 25 percent of all vehicles in the fleet and shuttle operations of each agency. (B) The strategy developed under subparagraph (A) shall be updated not less frequently than once every 2 years. . 6. Report Not later than 2 years after the date of enactment of this Act, and biennially thereafter, the Secretary and the appropriate agency heads shall submit to the appropriate committees of Congress a report that describes— (1) the location of— (A) any zero-emissions vehicle infrastructure acquired, installed, or operated, or planned to be acquired, installed, or operated, under section 3(b)(1); and (B) any zero-emissions vehicles acquired for the fleet of the Forest Service or the National Park Service under section 3(b)(2); (2) the amount of Federal funds expended to carry out each duty under section 3(b); (3) any allocation of costs or benefits between the Federal Government and private or nonprofit entities under an agreement entered into by the Secretary or the appropriate agency heads under section 3(b)(1); (4) the justifications for the expenditure of funds to carry out section 3 during the period covered by the report, including, with respect to any zero-emissions vehicle infrastructure installed during the period covered by the report, an analysis of each of the considerations under section 3(c); (5) if applicable, any challenges in acquiring the necessary workforce to install, operate, or maintain— (A) any zero-emissions vehicle infrastructure acquired, installed, or operated, or planned to be acquired, installed, or operated, under section 3(b)(1); and (B) any zero-emissions vehicles acquired for the fleet of the Forest Service or the National Park Service under section 3(b)(2); (6) with respect to each agreement for shuttle or other transportation services on or to covered land entered into by an appropriate agency head during the period covered by the report, how the appropriate agency head complied with the requirements of section 4