Mid-Century Educational Homogamy Squeeze

Robert Mare is the leading quantitative researcher on educational homogamy, the tendency of people with the same level of education to marry one another. His review of five decades of "educational assortative mating" in 1991 found that there was a significant increase in educational homogamy in the United States from the 1930s to the 1970s, then the rate went down a bit. He concluded that the key variable is how close graduation and marriage are. People who marry right out of school are much more likely to marry someone with the same amount of education. From 1930 to about 1970, graduation was getting later and marriage was getting earlier, which pushed the educational homogamy rate up. Since 1970, marriage age has been rising again, so educational homogamy has declined.