Wall St ends flat in short session, Dow ekes out record close

By Ryan Vlastelica

NEW YORK (Reuters) - U.S. stocks closed flat in a short session on Wednesday as investors found few reasons to push major indexes to their sixth straight day of gains despite strength in biotechs and bullish labor market data.

While both the S&P 500 and Dow touched intraday records, and the Dow closed at a slight record, the day's moves were slight and volume was light with many market participants already out for the Christmas holiday.

In a session that ended three hours early, about 2.5 billion shares traded on all U.S. platforms, according to BATS exchange data, well below the month-to-date average of 7.66 billion. Markets will reopen Friday.

Equities have been on a hot streak of late, with the Dow closing above 18,000 for the first time ever on Tuesday. The S&P 500 rose 5.5 percent over the past six sessions and has notched 51 closes this year, the most since 1995 and the fourth best in history.

Those gains have come on central bank assurances and improving economic data, a trend that continued with jobless claims on Wednesday. Initial claims for state unemployment benefits dropped 9,000 to a seasonally adjusted 280,000, their fourth straight week of declines, and below the forecast of 290,000.

"Equities are heading towards the year-end finale in a good position," said Terry Sandven, senior equity strategist at U.S. Bank Wealth Management in Minneapolis. "Fundamental and macro factors are supportive of higher equity prices, and clearly today if you look at the claims data which was generally in line with expectations, it still points toward an improving labor market."

Biotechs were the big gainers of the day, with the Nasdaq Biotech index up 1.6 percent in a partial rebound from the drop of nearly 7 percent over the previous two sessions. Celgene Corp rose 3.3 percent to $109.60 while Gilead Sciences added 2 percent to $91.29.

The Dow Jones industrial average rose 6.1 points, or 0.03 percent, to 18,030.27, the S&P 500 lost 0.29 points, or 0.01 percent, to 2,081.88 and the Nasdaq Composite added 8.05 points, or 0.17 percent, to 4,773.47.

Both the Dow and S&P closed out their sixth straight daily advance, the longest streak for the benchmark S&P since June.

Energy shares continued their recent weakness as crude oil lost 3.5 percent to $55.15 per barrel and hovered near its lowest level since 2009. The S&P energy index fell 0.8 percent; Exxon Mobil lost 0.9 percent to $93.78 while ConocoPhillips slid 1.3 percent to $70.13.

Declining issues outnumbered advancing ones on the NYSE by 1,542 to 1,453, for a 1.06-to-1 ratio on the downside; on the Nasdaq, 1,550 issues rose and 1,090 fell for a 1.42-to-1 ratio favoring advancers.

The benchmark S&P 500 index was posting 78 new 52-week highs and 5 new lows; the Nasdaq Composite was recording 96 new highs and 24 new lows.

(Additional reporting by Chuck Mikolajczak; Editing by Meredith Mazzilli)