Consumers' confidence in the economy remained weak in September after dropping to a post-recession low during the month before as Americans continue to worry about high unemployment and low wages.

The Conference Board, a private research group, said Tuesday that its Consumer Confidence Index was at 45.4, up slightly from a revised 45.2 in August. Economists surveyed by FactSet had expected a reading of 46. The August reading, which was the lowest since April 2009, was almost 15 points below July's reading of 59.2

A reading above 90 indicates the economy is on solid footing. Economists watch the number closely because consumer spending accounts for about 70 percent of U.S. economic activity.