Nov. 9--Trina Banks Session isn't unemployed -- at least, according to the ugly jobless numbers released Friday.

True, she works every day as a substitute teacher. But the former nonprofit executive has been searching for a job for two years.

Despite her master's degree, her networking know-how and her resume detailing an ambitious climb up the career ladder, Session hasn't been able to find a full-time job, whether it matches her skills and former pay or is entry level. The $300 she takes home weekly as a substitute is a fraction of her previous pay. And she said without the kindness of family members, she would be close to homelessness.

Unemployment, now more than 10 percent nationally, is at its highest level since the early 1980s. When you add in the unemployed who have given up looking for a job and part-time workers who want full-time work, the figure is 17.5 percent.

But even that number may grossly understate the number of additional people who, like Session, are facing underemployment -- a phenomenon that economists say is hurting a broad but often hidden swath of people.

They include:

- Retail, construction and other hourly workers whose work hours have been reduced.

- Full-time workers taking pay cuts for the same amount of work.

- Laid-off workers who have found new jobs that pay significantly less or offer fewer hours.

- Jobless professions who have taken unskilled, low-wage jobs.

- Contract workers getting less work or no contracts at all.

Underemployment is the "dirty secret behind the headline numbers," said Sean Snaith, an economist and forecaster at the University of Central Florida. It's hard to measure, but it's clearly having a big impact.

"Underemployment is a major problem coming out of this recession," he said. "Even as the economy recovers, employers ... will still keep people out of the payroll. Underemployment is what's going to really be behind the jobless recovery."

Anecdotally, he said, almost anyone can tell you about someone they know: a husband getting fewer contract jobs, a daughter picking up schedules with fewer and fewer hours at a retail job, a laid-off friend taking a job far below their skill set.

The statistics are elusive because underemployment is difficult to quantify, according to the U.S. Bureau of Labor Statistics. Even if many or most of the underemployed could be identified, it would still be difficult to quantify the loss to the economy of such underemployment, it said on its Web site.

It does track indicators such as people employed part-time but looking for full-time work.