Fewer students have started repaying their loans within a year of graduation even as the number of students borrowing has increased, according to a recent study.

The National Center for Education Statistics conducted a study examining the rates of borrowing and how quickly graduates begin repaying their loans over the past 15 years.

The report studied three groups of student loan borrowers in 1992-93, 1999-2000 and 2008-09. The percentage of recent college graduates who borrowed for their undergraduate education was higher in each successive cohort, according to the researchers.

The average amount of loans borrowed increased from $15,000 in 1992 to $24,700 in 2009.

Meanwhile, the repayment rate for graduates within the first year from graduating declined from 66 percent in 1992 to 60 percent in 2009, while the percentage of college students borrowing for undergraduate education increased 17 percent from 49 percent in 1992 to 66 percent in 2009.

There has been a corresponding increase in the percentage of students who still owes money but is not in repayment.

The largest increase in borrowing was for students attending for-profit colleges, with 90 percent of students in 2009 taking out loans compared to 70 percent in 1992

Among students in public and private nonprofit institutions of higher education, students who come from lower-income families are frequent borrowers.

The story also shows that in 2009, after the 2008 recession, a larger percentage of graduates in repayments faced higher monthly loan payments, about more than 12 percent of their monthly income than their counterparts in 1994 and 2001.

Starting salaries for the first-time borrowers remained stagnant over the period and actually declined from 2001 to 2009, with the average salary going from $33,200 in 1992 to $39,300 in 2001. It receded to $34,400 for the 2009 group.

Researchers used data collected from the Baccalaureate and Beyond Longitudinal Study, a federal survey which tracks outcomes for college students who have borrowed federal student loans.