Stock index futures were little changed on Tuesday as S&P 500 futures found support near their 50-day moving average following four days of losses on the benchmark index.

Investors also got some respite from trade data from China that reinforced the view the world's second-largest economy will avoid a hard landing.

Futures on the S&P 500 hit a session low below 1,374, testing support at the 50-day moving average for a third straight session. The closely-watched level stands currently above 1,371 on both the futures and cash markets.

The S&P 500 is up nearly 10 percent so far this year but has fallen 2.6 percent in the past four sessions as investors question the economy's strength and the U.S. Federal Reserve's resolve to continue flooding the market with easy cash.

Some analysts view the pullback as a buying opportunity, while others see it as the start of a long-awaited correction.

The market is trying to figure out whether or not this selloff has run its course, said Robert Pavlik, chief market strategist at Banyan Partners LLC in Palm Beach Gardens, Florida.

I think the near term focus is really a question of have we stabilized heading into the start of earnings season, he said.

Dow component Alcoa Inc , a bellwether for the industrial sector, unofficially kick-starts the quarterly earnings season after the closing bell.

U.S. economic data on Tuesday include wholesale inventories for February, due at 10 a.m. EDT (1400 GMT). Economists in a Reuters survey forecast a 0.5 percent rise versus a gain of 0.4 percent in January.

S&P 500 futures rose 1.1 points but were slightly below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures rose 13 points, and Nasdaq 100 futures added 7.75 points.

European markets, after being closed Friday and Monday, were catching up with global equity losses triggered by a soft payrolls report for March in the United States last week. An index of European stocks <.FTEU3> fell 1.2 percent. <.EU>

China returned to an export-led trade surplus of $5.35 billion in March, suggesting that a rebound in the global economy is lifting overseas orders just in time to compensate for a slowdown in domestic demand.

A Reuters poll on Monday showed most major Wall Street firms expect anemic growth in the U.S. jobs market and a struggling economic recovery to force the Federal Reserve to undertake another round of monetary stimulus.

Recent losses in the U.S. stock market were sparked by minutes from the Fed's March policy meeting that were interpreted as showing the central bank was less than keen to launch more stimulus.

U.S.-traded shares of Sony Corp dropped 8 percent to $18.50 in light premarket trading after the company forecast a record $6.4 billion net loss for the business year just ended.

On Monday the Dow and the S&P 500 extended losses to a fourth day, as investors took their cues from last week's disappointing jobs report, which raised fresh concerns about the U.S. economic recovery.

(Reporting by Rodrigo Campos; Editing by Chizu Nomiyama)