[NEW YORK] Wall Street opened little changed on Wednesday as investors paused after a day when the S&P 500 and the Nasdaq hit record highs and the Dow closed 0.4 per cent shy of its all-time high.

A rally since late June has left the S&P up nearly 7 per cent in 2016, as expectations of continued low interest rates encourage investors to buy into equities.

"Everybody is at the beach and they aren't even calling in trades anymore," said Kim Forrest, a senior equity research analyst at Fort Pitt Capital Group in Pittsburgh. "In times of low volumes, moves up or moves down are greatly exaggerated, because there is not enough participants to absorb those extra shares."

Trading volumes have been near year-lows since Monday as the second-quarter earnings season winds down.

Oil prices reversed course to trade slightly higher in choppy trading on Wednesday.

The dollar index fell for the second straight day as weak US productivity data on Tuesday somewhat dimmed the prospects of economic growth and would likely deter the Federal reserve from raising interest rates.

At 9:37 am ET (1337 GMT), the Dow Jones Industrial Average was down 3.01 points, or 0.02 per cent, at 18,530.04.

The S&P 500 was down 0.61 points, or 0.03 per cent, at 2,181.13.

The Nasdaq Composite was down 5.98 points, or 0.11 per cent, at 5,219.50.

Six of the 10 major S&P 500 indexes were higher, led by a 0.36 per cent rise in consumer staples.

Shares of Dow component Walt Disney fell 0.7 per cent to US$96.01, after the company reported results overnight and bought a 33 per cent stake in video-streaming firm BAMTech.

Yelp jumped 13 per cent to US$36.90 after the company reported a surprise profit and raised its full-year revenue forecast.

SunPower shares sank 30 per cent after the company swung to a second-quarter loss, lowered its full-year revenue forecast and said it would reorganize its business.

Perrigo dropped 11.4 per cent to US$84.44 after the company reported a lower-than-expected profit and slashed its earnings forecast.

JD.com jumped 8.6 per cent to US$24.28 after the company reported revenue within its forecast. The stock gave the biggest boost to the Nasdaq.

Advancing issues outnumbered decliners on the NYSE by 1,559 to 1,029. On the Nasdaq, 1,217 issues fell and 994 advanced.

The S&P 500 index showed eight new 52-week highs and two new lows, while the Nasdaq recorded 35 new highs and eight new lows.

REUTERS