title 5. (b) Allowances based on living costs and environment (1) In addition to basic pay, employees in Space Force positions who are citizens or nationals of the United States and are stationed outside the continental United States or in Alaska may be paid an allowance, in accordance with regulations prescribed by the Secretary of Defense, while they are so stationed. (2) An allowance under this subsection shall be based on— (A) living costs substantially higher than in the District of Columbia