U.S. consumer sentiment fell unexpectedly in early October, as high gasoline prices and the fallout from hurricane damage continued to take their toll, a report showed on Friday.

The University of Michigan's (search) preliminary October index of consumer sentiment fell to 75.4, according to sources who saw the subscription-only report. That was below a final September reading of 76.9 and Wall Street's median forecast of 80.0.

The survey's expectations component fell to 62.4 from 63.3 and Wall Street forecasts of 67.0. The index of current conditions fell to 95.7 from 98.1 in September and was below Wall Street forecasts for a slight rise to 99.5.

Confidence measures are used as an indicator of consumer spending (search), which makes up about two-thirds of overall U.S. economic activity. Consumer spending in turn is seen as an indication of strength or weakness in economic growth.