The S&P 500 index hit 1,400 for the first time in four years on Thursday as a strong run of economic data continues to cement a strong uptrend in equity markets.

Shares in Apple Inc hit a new all time high above $600 in early trading, with some analysts predicting the stock will move to $700 within 12 months.

Trading was volatile at the start of quadruple witching, the expiration and settlement of four types of equity futures and options contracts.

is important because of the trend, it confirms the upward bias in the market, said Peter Kenny, managing director at Knight Capital in Jersey City, New Jersey. There is a built in momentum trend as a result of the economic data.

1,400 marks the highest level for the S&P 500 since June 2008.

Labor Department data showed new claims for unemployment benefits fell back to a four-year low last week, and producer prices, excluding food and energy, were contained.

The Dow Jones industrial average <.DJI> rose 34.51 points, or 0.26 percent, to 13,228.61. The S&P 500 Index <.SPX> added 6.84 points, or 0.49 percent, to 1,401.12. The Nasdaq Composite <.IXIC> gained 15.43 points, or 0.51 percent, to 3,056.16.

The S&P 500 snapped a five-day winning streak on Wednesday after advancing nearly 4.0 percent during the run, as investors found little reason to extend a rally that took the benchmark index to four-year highs. But the index is up over 2 percent this week, its best since early February.

Manufacturing data in New York and the U.S. mid-Atlantic region also improved, according to regional Federal Reserve surveys.

Apple stock hit a new all-time high at $600.01, up nearly 2.0 percent from the previous day's close and up nearly 60 percent since mid-December.

The stock has been more volatile recently and on Thursday traded in a wide range between a fall of 0.9 percent and a rise of 1.8 percent. The stock last traded up 0.2 percent at $591.19.

The CBOE Apple VIX index <.VXAPL>, which tracks options on Apple's stock, leapt over 12 percent on Thursday and is up 70 percent over the last two days, hitting its highest since November - a possible indicator of more volatility ahead.

Helping transport stocks but hurting energy companies was news that Britain will cooperate with the United States in a bilateral agreement to release strategic oil stocks in an effort to prevent high fuel prices derailing economic growth in a U.S. election year, according to two British sources.

U.S. crude futures fell after the news and traded down 0.5 percent at $104.91. The Dow transport index <.DJT> rose 2.3 percent, while the S&P energy index traded flat.

Semiconductors moved higher, led by Advanced Micro Devices Inc , which jumped 6.2 percent to $8.24 after Jefferies upgraded the stock to a buy rating. The Philadelphia Semiconductor Index <.SOX> gained 1.8 percent.

Ross Stores Inc reported a higher profit for the holiday quarter as shoppers sought out popular clothing brands at discount prices, and the off-price chain forecast respectable sales and profit gains for this fiscal year. Shares dropped 0.5 percent to $55.26. The Morgan Stanley retail index <.MVR> lost 0.5 percent.

Three initial public offerings made their debuts on Thursday: cloud computing-based software company Demandware Inc , analog chipmaker M/A-Com Technology Solutions Holdings and Allison Transmission Holdings .

Demandware surged 52.5 percent to $24.40, M/A-Com advanced 9.6 percent to $20.69 and Allison Transmission rose 1.9 percent to $23.44.

(Editing by Theodore d'Afflisio)