U.S. stocks closed higher Monday, with consumer discretionary and health care stocks among the top gainers, as oil prices pared most of their overnight losses.
"I think the market's up because of crude," said JJ Kinahan, chief strategist at TD Ameritrade.
All three major averages reversed an opening decline to close at their highest levels of the year so far.
The Dow held about 106 points higher in the close, above the psychologically key 18,000 level for the first time since July 20, 2015. ( Tweet This ) Earlier, the index topped the level for the first time in intraday trade since July 21, 2015. Walt Disney contributed the most to gains in the index, followed by Home Depot and Chevron. Apple contributed the most to declines.
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"It's pretty amazing we're back to the levels we're at," Kinahan said. "The encouraging thing to me is we're getting strength from somewhere different every day."
U.S. crude oil futures settled down 58 cents, or 1.4 percent, at $39.78 a barrel for its first four-day losing streak since late March. Traders noted some support for crude, at least in the short term, from news that Kuwait significantly cut production due to an oil-worker strike.
Overnight, WTI fell more than 6.5 percent overnight after producers on Sunday failed to reach an output freeze agreement at a meeting in Doha, Qatar.