The WPA was a national program that operated its own projects in cooperation with state and local governments, which provided 10–30% of the costs. Usually the local sponsor provided land and often trucks and supplies, with the WPA responsible for wages (and for the salaries of supervisors, who were not on relief). WPA sometimes took over state and local relief programs that had originated in the Reconstruction Finance Corporation (RFC) or Federal Emergency Relief Administration programs (FERA). It was liquidated on June 30, 1943, as a result of low unemployment during World War II. Robert D. Leighninger asserted: "millions of people needed subsistence incomes. Work relief was preferred over public assistance (the dole) because it maintained self-respect, reinforced the work ethic, and kept skills sharp."