film, Rosie the Riveter, was released in 1944, borrowing from the Rosie theme. Impact During the Second World War According to the Encyclopedia of American Economic History, "Rosie the Riveter" inspired a social movement that increased the number of working American women from 12 million to 20 million by 1944, a 57% increase from 1940. By 1944 1.7 million unmarried men between the ages of 20 and 34 worked in the defense industry, while 4.1 million unmarried women between those ages did so. Although the image of "Rosie the Riveter" reflected the industrial work of welders and riveters during World War II, the majority of working women filled non-factory positions in every sector of the economy. What unified the experiences of these women was that they proved to themselves (and the country) that they could do a "man's job" and could do it well. In 1942, just between the months of January and July, the estimates of the proportion of jobs that would be "acceptable" for women was raised by employers from 29 to 85%. African American women were some of those most affected by the need for women workers. It has been said that it was the process of whites working alongside blacks during the time that encouraged a breaking down of social barriers and a healthy recognition of diversity. Postwar Women quickly responded to Rosie the Riveter, who convinced them that they had a patriotic duty to enter the workforce. Some claim that she forever opened the work force for women, but others dispute that point, noting that many women were discharged after the war and their jobs were given to returning servicemen. These critics claim that when peace returned, few women returned to their wartime positions and instead resumed domestic vocations or transferred into sex-typed occupations such as clerical and service work. For some, World War II represented a major turning point for women as they eagerly supported the war effort, but other historians emphasize that the changes were temporary and that immediately after the war was over, women were expected to return to traditional roles of wives and mothers. A third group has emphasized how the long-range significance of the changes brought about by the war provided the foundation for the contemporary woman's movement. Leila J. Rupp in her study of World War II wrote "For the first time, the working woman dominated the public image.