Greg Ip wrote, a while ago:
Washington Wire - WSJ.com: Portion of High-School Grads Heading to College Shrinks: A welcome surge in the share of high-school graduates going to college has come to a halt, at least for now. First, some background: College graduates earn more than high-school graduates, and that premium is a lot bigger than it was 20 years ago. There are numerous reasons but one might be that after rising for most of the postwar period, the share of the work force with college degrees stopped growing, constricting supply just as demand for highly skilled workers took off.
Earlier this decade, there were signs of a shift. Responding perhaps to both the college wage premium and the weak job market, the proportion of high-school students who enrolled in college the fall after they graduated rose from 61.7% in 2001 to 68.6% in 2005, the highest since data began in 1959. To be sure, many of those enrollees never finished college but on balance it suggested the supply of college graduates was about to head higher. But last fall, the college enrollment rate dropped back to 65.8%, the Bureau of Labor Statistics reported this week.
Exactly why is unclear. The tighter labor market ought to have encouraged some kids to take jobs instead of go to college. But the report showed just 46% of high-school graduates were working last fall, down from 49.3% the prior year. The proportion unemployed but looking for work rose to 13.7% from 11.4%, and the proportion neither working, looking for work nor in college also rose, to 12.3% from 9.9%...
It's not just that the college premium is bigger than it was a generation ago: it's roughly 90% compared to 30% a generation ago. A lot more people should be going to college, for any economist's definition of "should."