U.S. stock index futures advanced on Wednesday, pointing to a bounce from declines a day earlier when the Dow suffered its biggest drop in four months, after data from China and Boeing earnings eased concerns about sluggish global growth.

The China HSBC Flash Manufacturing Purchasing Managers Index (PMI) showed that growth shrank for a 12th straight month in October, but output was at a three-month high of 49.1 and order books at their most robust since April, signaling a strengthening recovery.

The data offset some concerns triggered by the Markit's composite Purchasing Managers Index, which showed Germany's private sector shrank for a sixth month in October.

Boeing Co shares climbed 3.3 percent to $75.20 in premarket trading after the commercial jet and defense giant reported earnings and raised its full-year 2012 outlook.

"With few bits of information that can motivate investors to begin buying again, when you consider you have the election coming up, you have the fiscal cliff and the problems that remain in Europe and China, you are just not getting enough good news to avoid air pockets like we've had the last couple of days," said Rick Meckler, president of investment firm LibertyView Capital Management in Jersey City, New Jersey.

"For the market to really tick up, you are going to need to a few very positive or at least some positive forecasts."

Corporate profits will remain in focus after declines on Tuesday. There have been a ream of disappointments in the earnings reported so far, particularly in the results of large multinationals.

A total of 43 S&P 500 companies are scheduled to report earnings on Wednesday, including Citrix Systems Inc , F5 Networks Inc and Symantec Corp after the close.

AT&T Inc posted third-quarter revenue that was below analysts' expectations, but its earnings increased from a year earlier.

Dow Chemical Co , the largest chemical maker in the United States, said Tuesday it would cut 5 percent of its workforce and shut 20 plants to counter a slowing global economy. Its shares advanced 3.3 percent to $29.50 in premarket trade.

Eli Lilly and Co reported quarterly earnings and sales below Wall Street expectations, hurt by higher taxes and generic competition for its Zyprexa schizophrenia drug.

S&P 500 futures rose 3 points and were above 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 added 30 points, and Nasdaq 100 futures added 7.25 points.

EMC Corp slumped 6.4 percent to $23.10 in premarket trading after the data-storage equipment maker reported third-quarter earnings that missed analysts' expectations.

With results in from 29 percent of S&P 500 companies, 37 percent have exceeded revenue forecasts, far below the 62 percent average, and just 57.2 percent of the S&P 500 names reporting so far have beaten earnings forecasts, according to Thomson Reuters data through Tuesday morning.

The current reporting season has seen the lowest percentage of companies exceeding estimates since the fourth quarter of 2001.

Economic data expected on Wednesday includes the U.S. flash Markit Manufacturing PMI for October at 8:58 a.m. EDT. Economists in a Reuters survey expect a 51.5 reading for the October Flash index versus 51.1 in the final September report.

At 10:00 a.m., investors will peruse September new home sales and the August home price index for continued signs the industry is returning to health.

Economists in a Reuters survey expect new home sales to show a total of 385,000 annualized units compared with 373,000 in August. The home price index had risen 0.2 percent in July.

European shares advanced on Wednesday, encouraged by Chinese data and bouncing back after a steep sell-off on Tuesday.

The China data helped trim declines in Asian shares, though investors remained wary due to weak corporate earnings worldwide and enduring worries over a global slowdown.

(Editing by Bernadette Baum)