The Rockville campus of Montgomery College. More affluent students are choosing two-year colleges, according to a Sallie Mae survey. (Jeffrey Porter/For The Washington Post)

Previous surveys from the student loan giant found families spending progressively more on college from the 2008 to 2010 academic years, despite the recession.

Why the sudden shift?

More families began moving to lower-cost schools in 2010-11, the survey said, with a sharply higher share of high-income students choosing community college. There was also a rise in the sheer number of low-income students, some of whom presumably were middle-income students a year earlier, the study said. It also found that middle- and high-income families are spending less out of their own pockets (and bank accounts), and low-income families are spending more.

The steepest decline in college spending came among upper-income families, those earning six-figure incomes, whose average outlay declined from $31,245 in the 2010 academic year to $25,760 in 2011.

Low-income families (earning $35,000 or less) reported increased college spending, from $17,404 in 2010 to $19,888 in 2011. That is a counter-intuitive finding, given the massive increase in need-based aid of recent years. The report suggests the increase could simply reflect that a broader share of survey respondents have low incomes.

According to the report, grants and scholarships made up 33 percent of all college spending, up from 23 percent a year ago, a huge increase that suggests need-based aid is playing a larger role in meeting college expenses. The share of families receiving grants rose from 30 percent to 46 percent — again, in a single year.

The share of middle-income families receiving grant aid rose sharply -- from 30 percent to 49 percent in that one-year span.

Families increasingly link education to earnings, so it’s no coincidence that enrollment rates tend to rise during recession. The share of families who “strongly agreed” with the statement that college is essential for earning (as opposed to learning) rose from 59 percent in 2010 to 70 percent in 2011.

The report is chock full of interesting stuff. A few highlights:

• Parent savings accounted for only 30 percent of the typical family’s college budget, with another 7 percent coming from parent borrowing. Another 26 percent came from student earnings, savings and borrowing. Scholarship dollars provided most of the balance.

• The share of students from high-income families going to community colleges — historically favored by students of modest means — nearly doubled in a single year, from 12 percent to 22 percent.

• The share of parents who said they were “willing to stretch” their college budgets shrank dramatically, from 64 percent in 2010 to 51 percent in 2011.

• The share of students who said their primary motive for college was to earn more money rose sharply, a one-year jump from 61 percent to 75 percent.