Grants made under this part shall be allocated among the States in accordance with a formula to be prescribed, by rule, by the Secretary, taking into account population and climate of each State, and such other factors as the Secretary may deem appropriate.

The total amount allocated to any State under subsection (a) in any year shall not exceed 10 percent of the total amount allocated to all the States in such year under such subsection (a). Except for the District of Columbia, Puerto Rico, Guam, American Samoa, and the Virgin Islands, not less than 0.5 percent of such total allocation to all States for that year shall be allocated in such year for the total of grants in each State which has an approved State plan under this part.