More Americans have fallen behind on consumer loans than at any time in nearly 16 years, as credit problems once concentrated in mortgages have spread into other forms of debt, according to the American Bankers Association.

In a quarterly study, the association said the percentage of loans at least 30 days past due rose to 2.65 percent in the fourth quarter, from 2.44 percent in the third quarter and 2.23 percent a year earlier.

The rate of delinquencies was the highest since a 2.75 percent rate in the first quarter of 1992.

“There’s no question that the economy is weakening beyond housing, resulting in the loss of household purchasing power,” said John Lonski, chief economist at Moody’s Investors Service.

“Deterioration of household credit should continue through 2008, though the rate may moderate,” he said. “If it intensifies, then the current recession may prove more severe than anticipated.”