The average annual interest rates charged on popular types of credit cards fell again last week, according to Bankrate.com. For low-interest cards, which have rates below the national average but are often offered only to customers with strong credit histories, the average APR declined to 11.33 percent, from 11.42 percent the week before.

Cash-back cards, which generally require a good-to-excellent credit rating for approval, saw their average APR drop to 13.51 percent, from 13.57 percent.