U.S. consumers have grown more optimistic, which could boost retail sales and the economy.

Friday's report from the University of Michigan says a measure of “consumer sentiment” rose to the highest level since before the recession began .

Economists say confident consumers are more likely to make purchases, which is important because consumer demand drives more than two-thirds of all U.S. economic activity.

A separate report from the Labor Department on Friday shows that rising gasoline costs boosted wholesale prices in September, but outside the volatile areas of food and energy, overall inflation was tame.