Stocks traded at the pace of a legendary Manhattan traffic jam today as thousands of New Yorkers took the week off to avoid the disruptions caused by the Republican National Convention.

A Commerce Department report showing Americans' incomes barely grew last month got much of the blame for an across-the-board decline in stock prices.

But Wall Street's real problem was all the people who simply aren't showing up for work this week because of the GOP convention. With polls claiming one in 10 New Yorkers planned to get out of town this week, the markets were operating at a fraction of their usual capacity.

Stock trading volumes began tapering off last week, with Thursday and then Friday setting successive lows for volume this year, according the Bloomberg news agency. Today trading set yet another new low record for the year, with New York Stock Exchange volume running almost 20 percent below last Monday.

Many investment firms urged workers to take the week off or work from home to avoid the hassles of terrorists threats, demonstrations and intense security precautions around the convention site at Madison Square Garden. That is miles from Wall Street, but thousands of investment industry workers come into town through Pennsylvania Station, which is right under The Garden.

The absentees potentially could make the markets less liquid and less stable if any major market-moving events occur. Today, however, the consumer income report was not bad enough to drastically impact stock prices and was partially offset by another Commerce Department report showing an improvement in consumer spending.

The government reports showed incomes grew just 0.1 percent in July, while spending increased by 0.8 percent. The spending growth was slightly better than expected, the income growth slightly worse.

Technology stocks were hurt by speculation that Intel Corp. will lower its revenue forecast for the remainder of the year when it issues a financial report on Thursday.

The Nasdaq Stock Market composite index fell 26 points to 1,836.49.

The Dow Jones industrial average dropped 73 points to 10,122.52.

The Standard & Poor's 500 stock index slipped almost 9 points to 1,099.15.

Crude oil prices also fell -- for the sixth time in seven days -- closing down 90 cents a barrel at $42.28.