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How hard has the Great Recession hit young adults in the U.S.? According to a report released Thursday by the Pew Research Center, only 54.3% of young adults aged 18 to 24 have a job. It’s the lowest rate since the government started keeping records in 1948.

Young Americans graduating from high school and college over the last several years have been confronting one of the worst job markets in decades. And while the recession has hurt almost every demographic in the U.S., those at the beginning of their working lives have found that, even more than other age groups, there just isn’t any work for them.

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The grim unemployment picture for young adults is clearly seen in Pew’s new report, which shows that slightly more than half of all 18- to 24-year-olds were employed at the end of 2011. That rate is only slightly higher than in 2010 (54%), but dramatically lower than the 62.4% rate of just four years earlier.

One of the reasons that rate is so low today is that many, faced with the prospects of unemployment, went back to school. Last year, 45.2% of young adults were enrolled in high school or college compared to 1990, when 31.3% were enrolled. Higher enrollment is probably a good thing for the economy long term, but it’s also a sign that many students felt they had no real hope in the current job market without more education.

But it’s also likely that many of those same students would like to be earning some money in between classes and can’t: Only 40.7% of college students have a job, down from 47.6% in 2007. (The employment rate for 18- to 24-year-olds not in school also fell, from 73.2% four years ago to 65%.) Unfortunately, fewer working students may mean they’re relying more on student loans to finance their educations.

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It’s worth noting that the official jobless rate for 18- to 24-year-olds reported by the Bureau of Labor Statistics was 16.3% last year, a figure that counts as unemployed only those who are actively seeking work, which generally doesn’t include full-time students. That figure is nearly double the 8.3% jobless rate for all age groups reported by the Bureau of Labor Statistics last week.

Just don’t worry too much about our country’s young adults, since they don’t worry all that much themselves. Despite their gloomy circumstances, Pew found, the group remains eternally optimistic. Of those aged 18 to 34, 88% of them say that they either earn enough money now or expect they will in the future. In contrast, 28% of those over 35 say they don’t believe they’ll make enough money in the future. According to Pew: “While young people are less likely now than they were before the recession to say they currently have enough income, their level of optimism is undiminished from where it was in 2004.” And that was three years before the recession hit them harder than anybody.