NEW YORK — A disappointing report on housing starts made investors nervous about the economy yesterday and sent stocks lower even as profits at many companies exceed expectations.

Stocks retreated from 2009 highs after the Commerce Department said applications for home building permits fell in September by the largest amount in five months. That is a discouraging signal for future construction.

Investors will get another measure of the housing market's health Friday with a report on sales of existing homes. After several months of upbeat data, the past few weeks have brought signs that a housing recovery could be slowing.