How Many P-51 Mustangs Were In Service With The US Air Force?

TheNorth American Aviation P-51 Mustang was a key fighter of the United States Army Air Forces (USAAF) in the Second World War. By the timeWWII came to an end, the USAAF (now the United States Air Force) claimed to have destroyed some 4,950 enemy aircraft in the air. That is a higher number than claimed for any other USAAF fighter in the European theater. So, how many Mustangs did the USSAF/USAF have in service?