U.S. consumer sentiment fell in August, the University of Michigan reported Friday.

The university’s final August reading dropped to 91.9 from 93.1 in July. The result was lower than the survey’s preliminary August reading of 92.9 and was the index’s lowest result since May.

Despite the decline, consumer sentiment remains relatively strong. Economists closely watch consumer-confidence indexes for clues on consumer spending, which accounts for about 70 percent of U.S. economic activity.