Stocks close lower, health care posts worst session since June 24

U.S. stocks closed lower on Wednesday, with health care shedding more than 1.5 percent, while investors eagerly awaited a speech from Federal Reserve Chair Janet Yellen .

The benchmark S&P 500 closed about 0.5 percent lower, with health care posting its worst trading day since June 24. Health care began falling sharply in afternoon trade after Democratic presidential nominee Hillary Clinton tweeted about the recent price hikes on EpiPens, marking the second time in about a year the former Secretary of State pressured the sector with a comment.

"We almost got to the point where maybe it was safe to get back into health care," said Art Hogan, chief market strategist at Wunderlich Securities. "It was like Hillary Clinton got something to react to rather than something she presented on her platform."

The Dow Jones industrial average fell approximately 60 points in choppy trade, with UnitedHealth Group (UNH) contributing the most losses.

"It's low volume. ... A quiet market is easily pushed around," said Robert Pavlik, chief market strategist at Boston Private Wealth. He also said: "I think the market is waiting a little bit on the edge of its seat for Yellen's speech."

"That's the number 1 thing markets are going to be focused on," said Matt Tuttle, chief investment officer at Tuttle Tactical Management, referring to Yellen's speech. "I don't think anyone has too much conviction ahead of that speech."

The Nasdaq composite closed about 0.8 percent lower, with the iShares Nasdaq Biotechnology ETF (IBB) shed 3.36 percent.

S&P health care sector 2-day chart

Source: FactSet

Stocks traded slightly lower for most of the session before health care and biotech began to slide.

"The biggest problem is there is no worthy news to move the market right now," said Bruce McCain, chief investment strategist at Key Private Bank.

"We've been in a very tight range and the VIX is low ... and that signals complacency," said Jeff Kravetz, regional investment strategist at the Private Client Reserve at U.S. Bank. He also said he was advising clients to be cautious heading into the fall.

Yellen is scheduled to speak on the U.S. economy and monetary policy Friday at 11 a.m. ET against a backdrop of recent hawkish rhetoric from two of her top lieutenants, New York Fed President William Dudley and Fed Vice Chairman Stanley Fischer.

"What's amazing is we've recently geared up for something big from the Fed, and then there's a big nothing," said JJ Kinahan, chief strategist at TD Ameritrade. He also said he expects Yellen's speech to be a non-event.

Key Private Bank's McCain said investors are hoping Yellen does not say too much that could move the market. "It's a boring time in the markets and investors are hoping it stays boring because prices keep going up," he said.

"They all basically opened the door for a rate hike in 2016," said Ernie Cecilia, CIO at Bryn Mawr Trust. "It seems ... they're trying to put the word out that a rate hike may be possible."

"I think the market is handling it pretty well," he said.

U.S. closed slightly higher on Tuesday, with the Nasdaq hitting a new all-time intraday high of 5,275.74, while the S&P came within one point of breaking its all-time high of 2,193.81, reached last week.

That said, stocks have traded in a very tight range amid low volume and low volatility. The S&P posted its 33rd straight session without closing at least 1 percent higher or lower on Wednesday.

"This is still a market with a lot of risk," said James Abate, CIO at Centre Funds. He noted that, because sovereign yields are so low, investors have turned to equities in their search for yield. The main problem here, Abate said, is "10 years of income can be wiped out in two days."

"Look at Bristol-Myers (BMY) and Corrections Corp. (CXW) These are names that were bought mainly for yield," he said. Both stocks are in bear market territory, or down at least 20 percent from their 52-week high.

Investors also watched oil markets, with U.S. crude (New York Mercantile Exchange: @CL.1) settling 2.77 percent lower at $46.77 a barrel after the Energy Information Administration said U.S. crude stockpiles rose by 2.5 million barrels.

On the data front, existing home sales for July fell 3.2 percent, more than expected. New home sales data, released Tuesday, reached their highest level in almost nine years.

"I think that we are on a much better place when this market reacts to good news (housing yesterday) in a constructive way. That's a very good sight and an important inflection point," Art Hogan, chief market strategist at Wunderlich Securities, said in an email.

In corporate news, RBC (Toronto Stock Exchange: RY-CA) reported better-than-expected quarterly results, with funds set aside to cover bad loans falling thanks to higher oil prices.

La-Z-Boy (LZB) reported a 1.9 percent drop in same-store sales for its fiscal first quarter. The firm also posted adjusted earnings of 28 cents a share on revenue of $341 million, missing expectations. La-Z-Boy shares fell more than 12.5 percent in afternoon trade.

U.S. Treasurys traded mostly flat, with the two-year note yield near 0.75 percent and the 10-year yield around 1.55 percent. The U.S. dollar rose against a basket of currencies, with the euro near $1.126 and the yen around 100.43.

The Dow Jones industrial average (Dow Jones Global Indexes: .DJI) closed 65.82 points lower, or 0.35 percent, at 18,481.48, with UnitedHealth Group leading decliners and Nike the biggest riser.

The S&P 500 (^GSPC) fell 11.46 points, or 0.52 percent, to 2,175.44, with health care leading nine sectors lower and utilities closing flat.

The Nasdaq (^IXIC) dropped 42.38 points, or 0.81 percent, to 5,217.69.

About three stocks declined for every advancer at the New York Stock Exchange, with and exchange volume of 744.8 million and a composite volume of 3.097 billion at the close.

Gold futures for December delivery settled $16.40 lower at $1,329.70 per ounce.

On tap this week:

*Planner subject to change.

Wednesday

Earnings: HP, Heico, Williams-Sonoma, Workday

Thursday

Earnings: Toronto-Dominion Bank, Canadian Imperial Bank, Tiffany, Movado, Burlington Stores, Dollar General, Dollar Tree, Michaels Cos, Autodesk, GameStop, Pure Storage, Splunk

8:30 a.m. Initial claims, durable goods

1 p.m. $28 billion 7-year note auction

Friday

Earnings: Big Lots (BIG)

Fed Chair Janet Yellen speaks at Jackson Hole, Wyoming

8:30 a.m. Real GDP Q2 (second); international trade

9:45 a.m. Services PMI

10 a.m. Consumer sentiment

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