Outstanding consumer credit rose at annual rate of 6 percent in August, fueled by increased in credit-card debt, the Federal Reserve reported.

Nonrevolving consumer credit, which includes auto loans, increased at an annual rate of 4.75 percent, or $6 billion. In July, it rose by a revised 3.1 percent.

Interest rates at auto finance companies for new cars have hit a four-month low of 4.15 percent. In May, the Federal Reserve had interest rates at 4.86 percent.

After trending down from May to July, Loan maturities hit their highest point since the fourth quarter of 2006 at 62.6 months. The loan-to-value ratio also increased, rising from 92 percent in July to 94 percent in August.

Amount financed also continued its upward trend, increasing by $1,793 since June to $28,722 in August.

Nonrevolving consumer credit hit $1.557 trillion in August, up almost $20 billion from July. Finance companies represented $477 billion of that total, a $4 billion increase from last month. Commercial banks represented the second largest segment, up $8 billion from July at $435 billion. Pools of securitized assets made up $236 billion, a $1.5 billion increase from last month. Credit unions also increased their presence by $2 billion from July to $209 billion. Federal government and Sallie Mae increased by $2 billion from July, together representing about $96 billion, and savings institutions and non-financial businesses remained steady at about $57 billion and $46 billion, respectively.