Not every Ph.D. student aspires to a career as a tenured college professor. But in plenty of fields, particularly the humanities, spending your life buried up to your elbow patches in books and papers is the gold standard of success. So while breaking down the National Science Foundation's data for my last two pieces on the job market for doctorate holders, I took a bit of time to look at just what fraction of new graduates were landing jobs in the academy.

The good news? The numbers have only dropped a few percentage points in 20 years. The bad news? They were pretty low to begin with. 

Keep in mind, 34 percent of all soon-to-graduate Ph.D.'s didn't report having a job or postdoctoral appointment in the NSF's survey. At least some of those students probably landed at a college or university eventually. But long term, if you graduated in the class of 2011, your chances of living the academic dream appear to have been pretty slim. 

The available data on long-term career outcomes for Ph.D.'s aren't great. But back in 1999, a study titled Ph.D.'s -- Ten Years Later surveyed thousands of one-time doctoral students about how they'd fared in the workforce a decade or more after graduation day. These were men and women who'd received their diplomas sometime between 1982 and 1985, when the market was a bit less red in tooth and claw. And even in those days, their experience showed that without a fast early start, your chances of successfully scaling the ivory tower and reaching tenure were pretty slim. At the time 53 percent of all Ph.D.'s said they had intended to become professors. As this table (apologies for the awkward angle) showed, only about half of that group had obtained tenure within ten-to-fourteen years, while 33 percent weren't in academia at all. 

With tenure relatively rarer than it was 30 years ago, it's fair to assume that an even larger portion of tomorrow's full professors will come from the Ph.D.'s who land academic jobs off the bat. And as we've seen, that group is getting pretty small.

Homepage image: A Harvard student sells a T shirt that reads "No one ever says, 'I want to go to Yale when I grow up'" (Reuters/Jessica Rinaldi)