By Riva Gold and Daniel Huang

U.S. stocks fell Monday, capping a month of declines for major indexes.

The Dow Jones Industrial Average fell for a third consecutive month, its longest stretch of declines since 2011. The S&P 500 recorded its worst month since January, and the Nasdaq Composite snapped a three-month winning streak.

On Monday, investors appeared cautious at the start of a busy week that includes earnings results, central-bank meetings and the monthly U.S. jobs reportFriday, and ahead of next week's U.S. election.

The Dow industrials fell 19 points, or 0.1%, to 18142 on Monday. The S&P 500 and the Nasdaq Composite Index edged down less than 0.1%.

"Volumes are much lighter than usual," said John Brady, managing director at brokerage R.J. O'Brien, continuing a trend of slow trading in recent weeks. As of Friday, daily U.S. stock-trading volumes in October were below the 2016 average, according the WSJ Market Data Group.

Better-than-expected earnings results have pulled in some investors, but "I'm not sure if anything is going to be a bigger deal this week than who runs the country for the next four years," Mr. Brady said.

Around 300 companies in the S&P 500 have reported their quarterly earnings so far, according to FactSet, with more than 100 due this week.

Zimmer Biomet Holdings was the biggest decliner in the S&P 500, with shares falling 14% after the medical-device maker announced disappointing sales and cut its sales guidance for the year.

U.S. crude for December delivery declined 3.8% to $46.86 a barrel -- the biggest drop since Sept. 23 -- on doubts about whether the Organization of the Petroleum Exporting Countries would reach a consensus on cutting production. Energy firms in the S&P 500, down 1.2%, led sector declines.

Shares of oil-field-services company Baker Hughes fell 6.3% on news that it had reached a deal to combine with the oil-and-gas business of General Electric. Shares of GE fell 0.4%. The Wall Street Journal reported last week that the companies were in talks.

Shares of Level 3 Communications rose 3.9% after CenturyLink said it reached a cash-and stock deal to buy the communications company for roughly $25 billion. Shares of CenturyLink fell 13%.

The moves followed a series of high-profile deals announced last week, while Japan's three largest shipping companies also said Monday that they would merge their container-shipping operations.

Recent improvements in bank earnings and a flurry of mergers and acquisitions are helping support sentiment around the stock market, said Benjardin Gärtner, head of equities at Union Investment.

"It reflects good financing conditions, and more confidence in the economic and business outlook," Mr. Gärtner said.

Financial shares in the S&P 500 rose 2.2% in October, the best performer of the month. Telecom, one of the leaders in the first half of the year, recorded the biggest fall.

The Stoxx Europe 600 fell 0.5% Monday, with the oil and gas sector leading declines. The index lost 1.2% for the month.

Japan's Nikkei Stock Average fell 0.1% Monday but rallied 5.9% in October -- its biggest monthly gain since July.

The Bank of Japan concludes its policy meeting on Tuesday, while the Federal Reserve ends its latest meeting Wednesday. No action is expectedon interest rates just ahead of the U.S. election, but many investors are expecting a rate rise in December.

The Bank of England meets Thursday, with officials expected to announce whether they will ease policy further after launching a multipronged stimulus in August.

Government bonds firmed after a selloff last week pushed yields to five-month highs. The yield on the 10-year Treasury note fell to 1.834% from 1.847% on Friday. Yields are up from 1.605% at the end of September -- their biggest monthly gain since June 2015. Yields move inversely to prices.

Write to Riva Gold at riva.gold@wsj.com and Daniel Huang at dan.huang@wsj.com

(END) Dow Jones Newswires

October 31, 2016 16:28 ET (20:28 GMT)

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