WASHINGTON (Reuters) - U.S. consumer confidence unexpectedly fell in September amid mounting worries over the health of the labor market.

The Conference Board said on Tuesday its consumer confidence index dropped to 98.7 this month from an upwardly revised 105.6 in August. The decline was the largest since August 2021. Economists polled by Reuters had forecast the index rising to 104.0 from the previously reported 103.3.

"The deterioration across the index's main components likely reflected consumers' concerns about the labor market and reactions to fewer hours, slower payroll increases, fewer job openings, even if the labor market remains quite healthy, with low unemployment, few layoffs and elevated wages," said Dana Peterson, the chief economist at the Conference Board.

The share of consumers who viewed jobs as being "plentiful" dropped to 30.9% from 32.7% in August. Some 18.3% of consumers said jobs were "hard to get," up from 16.8% last month.

The Federal Reserve last week cut interest rates by 50 basis points to the 4.75%-5.00% range, the first reduction in borrowing costs since 2020, which Fed Chair Jerome Powell said was meant to demonstrate policymakers' commitment to sustaining a low unemployment rate.