Overall, the unemployment rate for workers with a college degree is about half the rate of those who hold just a high school diploma, but that gap appears to narrow for older, long-term unemployed workers. From an article by Arthur Delaney in The Huffington Post yesterday:

[A]dvanced degrees can lose their talismanic power. Once they become unemployed, college-educated workers are just as likely as high school grads to wind up unemployed for an extended period of time. During the year ending last June, 12.4 percent of jobless workers with high school diplomas had been out of work 99 weeks or longer, according to a Congressional Research Service report. Among unemployed Americans with a bachelor’s degree, 11.3 percent had been jobless 99 weeks or longer — a statistically insignificant difference. (my emphasis)

Delaney speculates that one of the reasons for this statistical narrowing is that workers with just a high school education are more likely to leave the labor force, which then reduces the proportion of those workers who count as officially unemployed. Another possibility, he writes, is that that “since a majority of new jobs created during the economic recovery are lower-paying and lower-skilled, they are easier for less-educated workers to learn, while higher-educated workers are simultaneously being more selective about the jobs they’re willing to work.”