In June 1944, the Manhattan Project employed some 129,000 workers, of whom 84,500 were construction workers, 40,500 were plant operators and 1,800 were military personnel. As construction activity fell off, the workforce declined to 100,000 a year later, but the number of military personnel increased to 5,600. Procuring the required numbers of workers, especially highly skilled workers, in competition with other vital wartime programs proved very difficult. In 1943, Groves obtained a special temporary priority for labor from the War Manpower Commission. In March 1944, both the War Production Board and the War Manpower Commission gave the project their highest priority.