Get a job. It's one of the more common prescriptions you'll hear offered up to students who worry about the cost of a college education these days. And it makes a certain degree of sense. Sure, working too much is one of the leading factors associated without dropping out. But working at least a few hours each week is good for a resume and your bank account.
There's a similar trend among the part time students, who are traditionally more likely to work. Again, their overall employment level took a big dip once the economy went to hell. (Apologies for this, but because I've entered data in 5 year intervals, the second chart actually smooths over a 5 percentage point drop and recovery that occurred between 2000 and 2005).
I don't want to over-interpret these numbers. There are a whole host of factors that could influence the proportion of students working in a given year, from the economy, to the availability of financial aid, to cultural issues. It could potentially be self-selection at work: a lot of students today might just assume they can't find work and so don't try. It's also possible that the job openings that exist don't pay enough or aren't sufficiently convenient to interest most undergrads.
But here's my take: There are a limited number of jobs that are open to students (a college town can only have so many barristas, after all), and more students than ever to compete for them. Meanwhile, it's hard time for anyone to get work, especially those who don't have a degree. Perhaps we shouldn't expect it to be any easier for young people still looking to earn theirs.
*Because of methodological issues, the DOE data on hours worked has some holes. As a result, the bottom three lines on each chart may not add up to the top line figure.