NEW YORK (CNNMoney.com) -- Stocks crept lower Thursday morning, as investors showed some caution after a four-day advance in the face of a mild August retail sales report.

The Dow Jones industrial average (down 39.31 to 11,504.01, Charts) lost around 0.3 percent nearly an hour into the session, while the broader Standard & Poor's 500 (down 2.65 to 1,315.42, Charts) index and the Nasdaq composite (down 3.41 to 2,224.26, Charts) both saw smaller declines.

A four-session advance had left the major market gauges at four-month highs by the end of Wednesday's session.

After such a run, stocks may have been a bit vulnerable Thursday.

August retail sales rose 0.2 percent in the month, after having increased 1.4 percent in the previous month, as higher oil and gas prices and increased worries about the economy during the month cut into consumer spending.

Economists surveyed by Briefing.com thought sales would fall 0.2 percent.

Sales excluding autos rose 0.2 percent in the month, after rising 1 percent in July. That was short of forecasts for a rise of 0.3 percent.

Although the August report is outdated - in September, oil prices have slumped and sales are expected to improve - it still unnerved investors sensitive to signs of a slowing economy.

Investors were also gearing up for Friday's report on consumer prices, a key reading on inflation, ahead of next week's Federal Reserve policy meeting.

Stock declines covered a number of sectors, with 23 out of 30 Dow issues falling, led by Boeing (down $1.11 to $75.21, Charts), Honeywell (down $0.31 to $38.95, Charts) and the other economically-sensitive issues that had risen most during the recent rally.

Components Boeing (down $1.09 to $75.23, Charts) and General Electric (down $0.30 to $34.54, Charts) were downgraded, according to Reuters, and that added to the overall early weakness.

Separately, GE said it was selling its advanced materials unit to private equity firm Apollo Management for $3.8 billion.

Bear Stearns (down $0.01 to $136.21, Charts) reported higher quarterly earnings that rose from a year ago and topped estimates. However, the stock declined after several up days for the bank sector.

Market breadth was negative. On the New York Stock Exchange, losers beat winners nine to five on volume of 270 million shares. On the Nasdaq, decliners topped advancers two to one on volume of 400 million shares.

U.S. light crude oil for October delivery rose 7 cents to $64.04 a barrel on the New York Mercantile Exchange.

COMEX gold for December delivery fell $3 to $593.30 an ounce.

Treasury prices were flat, with the yield on the 10-year note at 4.76 percent.

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