Foreign Per Diem Rates
Maximum rates of per diem allowances for travel in foreign areas are established by the Secretary of State. These rates apply to all U.S. Government employees and contractors. For regulations pertaining to these rates, see the Federal Travel Regulations (Chapter 301-7) as established by the General Services Administration and implementing regulations established by Federal Agencies, (Foreign Affairs Agencies - See 6 FAM 150; Defense Department Agencies - See Chapter 4 of the JFTR, Vol 1, for Members of the Uniformed Services and JTR, Vol 2, for Civilians.)
Current information can be found at the U.S. Department of State.
Go to the Manual of Business Procedures Section 70 to view the proportions.