We present the first estimates of the returns to years of schooling before 1940 using a large sample of men and women, employed in a variety of sectors and occupations, from the Iowa State Census of 1915. We find that the returns to a year of high school, and to a year of college, were...

The second transformation' of U.S. education the growth of secondary schooling occurred swiftly in the early 1900s and placed the educational attainment of Americans far ahead of that in other nations for much of the twentieth century. Just 9 percent of U.S. youths had high school diplomas in...