Australian economist John Quiggin corrects the often-stated statistic that more US students are attending college. While it is true that more Americans have a college degree, now over 30 percent, up from less than 20 percent in the early 1980s, the reason isn't that students are now attending college in greater numbers. What has happened is that many people educated before World War II, when few people finished college, are no longer living. As a result, the current population contains a larger percentage of people who graduated from college in the 1950s and 1960s when, indeed, college attendance sharply increased.
However, since about 1970, the proportion of young people graduating from college has been relatively stable. Looking at the single age group, 25 - 29, those with a college degree has remained at about 25 to 30 percent since then-- although there have been notable increases in college graduation by women and some minority groups.
These statistics demonstrate the importance of taking into account cohorts (that is age groups) as well as the entire population. In this case, the rising number of past college graduates masks a leveling off in attendance by the more recent generation. These statistics are important for debates about the role of college as vehicle for economic advancement.