* Apple shares edge higher after results, holiday outlook
* Aetna earnings miss expectations, U.S. Steel swings to loss
* Case-Shiller home prices, consumer confidence data on tap
* Futures: Dow up 3 pts, S&P down 0.2 pt, Nasdaq down 1.25 pt
NEW YORK, Oct 29 (Reuters) - U.S. stock index futures were flat on Tuesday, suggesting the market's recent rally may have run out of steam with corporate earnings failing to spur new optimism with the S&P 500 near record levels.
* Equities have been on a tear for the past few weeks, climbing on expectations the Federal Reserve will keep its stimulus in place when it meets this week. That policy, which has fueled the market's advance throughout the year, has been enough to offset an earnings season with seemingly as many disappointments as bright spots.
* Apple Inc, the most valuable U.S. company by market cap, late Monday posted a decline in its fourth-quarter earnings and margins. However, the tech titan also forecast first-quarter revenue of $55 billion to $58 billion, outpacing Wall Street's forecast for about $55.65 billion. Shares rose 0.4 percent to $532 in premarket trading.
* With half of S&P 500 companies having reported, 69.1 percent have topped profit expectations, above the long-term average of 63 percent, according to Thomson Reuters data. However, only 53.9 percent have beaten revenue estimates, below the 61 percent rate since 2002.
* S&P 500 futures fell 0.2 point 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 3 points and Nasdaq 100 futures slid 1.25 point.
* The S&P has climbed 6.4 percent since Oct. 8, when it hit its lowest point during the U.S. government's partial shutdown and the debate over raising the debt ceiling. The benchmark index is up 23.6 percent for the year so far, hitting a series of all-time highs. The Dow is less than 1 percent away from its all-time closing high.
* The gains may make further advances harder to come by, especially with earnings struggling to serve as broader market catalysts.
* Aetna Inc reported adjusted third-quarter earnings that missed expectations and gave a full-year profit outlook that was largely below estimates.
* U.S. Steep Corp late Monday swung to a third-quarter loss, hurt by a goodwill impairment charge, while Seagate Technology Plc reported first-quarter earnings and sales that missed expectations and gave a revenue outlook that was also below consensus.
* Investors are also looking ahead to the August read on home prices with S&P/Case Shiller data at 9 a.m. (1300 GMT), as well as September retail sales at 8:30 a.m. and the Conference Board's October consumer confidence data at 10.
* Home prices are seen rising 0.6 percent while retail sales edge 0.1 percent higher. The consumer confidence index is seen coming in at 75, down from last month's 79.7 reading, which was before the partial government shutdown.