1 in 5 households now owe student debt, new Pew Research study shows Forty percent of U.S. households headed by someone younger than age 35 owed student debt in 2010 - double the percentage from 20 years ago, according to a new Pew Research Center analysis that found a record one in five households hobbled by student debt. "We know the total amount of student debt has been rising, but what this study does is help us get a handle on who owes it," said Richard Fry, a researcher with the Pew Center. Outstanding student loans have topped $1 trillion, and rising tuition costs have spurred colleges and students to call for reforms. "It's been a hard labor market for everyone, but particularly for 18- to 20-year-olds, who have not been able to find work or find work in their qualified field," Fry said. View the Pew Research Center's complete report (Pdf) Households headed by someone younger than age 35 have by far the highest share of the debt among the age groups, Fry said. He said 70 percent of the total debt was owed by households headed by those under age 45. Among households owing student debt, the average outstanding student loan balance edged upward to $26,682 in 2010 from $23,349 in 2007, data show. Fry said incidence of student debt increased in nearly every demographic and economic category since 2007, but households with incomes less than $21,000 were hardest hit. "While households with higher incomes also had student debt, they were able to shed other debt obligations," he said. Other key findings: In 2010, nearly 90 percent of the debt was owed by households whose head had completed at least some college education and almost 70 percent was owed by households whose head had finished college. In 2009-10, 51 percent of full-time, first-time undergraduate students had a student loan; that was up 43.5 percent in 2006-2007. Most debtor households had less than $50,000 in outstanding student debt in 2010, but the share of households owing elevated amounts increased. For example, in 2007, 10 percent of student debtors owed more than $54,238. By 2010, 10 percent of student debtor households owed more than $61,894 (figures are adjusted for inflation). The study released is based on the Survey of Consumer Finances, conducted every three years and sponsored by the Federal Reserve.