WASHINGTON (AP) - Federal Reserve Chair Janet Yellen says while many savers have been frustrated by years of low interest rates, they were needed to boost the economy after the Great Recession.

WASHINGTON (AP) Federal Reserve Chair Janet Yellen says while many savers have been frustrated by years of low interest rates, they were needed to boost the economy after the Great Recession.

In a letter to consumer advocate Ralph Nader, Yellen says the low rates helped create millions of jobs by lowering borrowing costs for businesses and consumers.

The Fed has indicated it may soon be ready to begin raising rates. Yellen reiterates that subsequent rate hikes will be gradual.

Yellen was responding to a letter from Nader, who said he was writing on behalf of frustrated savers who have been getting near zero interest on their bank and money market savings accounts.