By William Watts and Victor Reklaitis, MarketWatch

Energy shares hit as crude slides; ISM weaker than forecast

U.S. stocks edged lower Monday, weighed down by weak economic data and a further slump in crude-oil prices.

Stocks dipped further after the Institute for Supply Management's closely watched manufacturing survey for July came in weaker than expected. Ahead of the opening bell, data from the Commerce Department showed personal spending rose slightly less than expected in June, while income was slightly above forecasts.

The S&P 500 was virtually flat at 2,102 in early action, while Dow industrials lost 49 points, or 0.3%, to 17,641. The Nasdaq Composite gained 6 points, or 0.1%, to 5,134.

Energy shares were hardest hit, following through on a Friday decline as crude-oil prices continued to tumble.

On Friday, the S&P 500 closed down 0.2% (http://www.marketwatch.com/story/us-stocks-sp-eyes-2-rise-for-month-but-month-end-volatility-seen-2015-07-31), dragged lower by the energy sector, but the benchmark gained 1.2% for the week and 2% for the month.

The benchmark stands about 1.3% off its record close in May, having traded in a narrow range for several months. More range-bound trading, or "numbness (http://www.marketwatch.com/story/golds-fire-sale-offers-refuge-on-feds-bumpy-road-to-rate-hikes-2015-07-31)," as a recent Need To Know column called it, could be ahead until Friday, with investors staying on the sidelines as they wait for the monthly U.S. jobs report due that day.

While Greece's stock market plunged as trading reopened, investors in other markets appeared to take that largely in stride.

What strategists are saying: "Over the past few months, the U.S. equity markets have been undulating inconclusively between 2050 and 2130.'" said Sam Stovall, U.S. equity strategist for S&P Capital IQ, in a note released Monday. He isn't that upbeat about what could happen this month.

August historically has been "among the worst performing months," and some indicators suggest more volatility ahead, Stovall said. Investors also "have been in a 'risk-off' mind-set since the final new high was established in May."

"Another month has gone by, and U.S. equities are still awaiting a resolution to their nine-month trading range," said Jonathan Krinsky, chief market technician for MKM Partners, in a note Sunday.

He said the difference between the top- and worst-performing industries in the S&P 500 continues to grow. "At some point, this divergence needs to be rectified, but for now the beat goes on," Krinsky wrote.

Read: 'Pipsqueak' Greece gets slammed, fueling fears over U.S. markets (http://www.marketwatch.com/story/get-ready-for-us-bubble-to-burst-as-pipsqueak-greece-gets-slammed-2015-08-03)

Other markets: Asian shares closed lower Monday (http://www.marketwatch.com/story/asian-markets-fall-as-chinese-factory-data-prompts-jitters-2015-08-03) after disappointing Chinese manufacturing data and a continued slide in commodity prices. European equities mostly gained (http://www.marketwatch.com/story/european-stocks-edge-up-greek-index-slides-as-trading-resumes-2015-08-03) even as Greek stocks plunged as trading resumed in Athens (http://www.marketwatch.com/story/greek-stock-market-dives-after-trading-resumes-2015-08-03).

Crude-oil futures were showing a sizable drop (http://www.marketwatch.com/story/oil-falls-to-4-month-low-hit-by-data-on-china-rigs-2015-08-03), while gold dipped and the dollar was little changed.

Economic news: The Commerce Department on Monday said personal spending by U.S. consumers rose 0.2% in June (http://www.marketwatch.com/story/consumers-increase-spending-a-mild-02-in-june-2015-08-03), while personal income grew by 0.4%. Economists polled by MarketWatch had forecast a rise of 0.3% for both measures.

A July reading for Markit's purchasing managers' manufacturing index is expected at 9:45 a.m. Eastern, followed by releases at 10 a.m. Eastern for June construction spending.

The Institute for Supply Management's July manufacturing index fell to 52.7% (http://www.marketwatch.com/story/early-release-of-ism-index-shows-drop-to-527-in-july-2015-08-03) from 53.5% in June, news reports said. That is below the forecast of 53.7% expected by economists. See:

As for Federal Reserve speakers, Fed Gov. Jerome Powell is scheduled to give a speech on the liquidity of the Treasury bond market at 10:50 a.m. Eastern.

Stock movers: Shares of Tyson Foods Inc.(TSN) fell more than 9% after the meatpacker missed profit expectations and cut its full-year outlook (http://www.marketwatch.com/story/tyson-profit-and-sales-fall-short-lowers-outlook-2015-08-03).

Shares of Fiat Chrysler (FCA.MI) rose 2.4% after the company reported July U.S. auto sales.

Read more in MarketWatch's Movers & Shakers column (http://www.marketwatch.com/story/aig-tyson-clorox-earnings-in-focus-2015-07-31)

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