As of March 1, 2008, the United States had 159,700 military personnel deployed in Iraq, according to DOD statistics compiled in a newly authored Congressional Research Service (CRS) report that compiles Pentagon figures on US force levels in Iraq. 134,900 of the troops present in March were active duty personnel, while 24,800 were National Guard and Reserves, CRS adds. The CRS document, entitled "U.S. Forces in Iraq" is available in full below, and was made available by the Federation of American Scientists. The document also contains breakdowns of DOD troop-level data over time as well as a table showing the Pentagon's slated troop rotations of troops in Iraq for 2008.
Below is the opening summary of the CRS report:
Varying media estimates of military forces in Iraq have raised concerns about the actual number of troops deployed in Operation Iraqi Freedom (OIF). Interest in troop level deployments continue in 2008. Last year, a major announcement on a surge in troop deployments to Iraq by the President Bush included a planned gradual increase of more than 20,000 U.S. troops on the ground in Baghdad and Anbar province over several months. Since the “new strategy for Iraq” speech by the President on January 10, 2007, troop deployments gradually increased during the months of February through October in 2007 but decreased beginning in November 2007. This report provides solely Department of Defense (DOD) statistical information on U.S. forces serving in Iraq. It also provides brief official information on the military units scheduled for the next rotation of duty into Iraq. As of March 1, 2008, according to DOD, the United States had 159,700 troops stationed in Iraq — 134,900 active component and 24,800 National Guard or Reserves. For security reasons, DOD does not routinely report the composition, size, or specific destination of military forces deployed to the Persian Gulf. This report will be updated upon receipt of new DOD data. For additional information on U.S. forces, see RL34387, Operation Iraqi Freedom: Strategies, Approaches, Results and Issues for Congress, by Catherine Dale.
Read the whole six-page document here: RS22449.pdf.