* Dow up 4 pts, S&P off 2.5 pts, Nasdaq down 6.5 pts
June 21 (Reuters) - U.S. stock index futures were lower on Wednesday as oil prices hovered near seven-month lows and were headed for their largest slide in the first half of any year since 1997.
* Oil has lost 20 percent in value this year as investors discount evidence of strong compliance by OPEC and non-OPEC producers with a deal to cut global output.
* The S&P energy index, which has fallen 13.52 percent this year, is the worst performing sector among the 11 major indexes.
* Investors are also concerned about the pace of future interest rate hikes as a tug-of-war between inflation and the future of financial stability plays out among the Federal Reserve's policymakers.
* Dallas and Chicago Fed chiefs Robert Kaplan and Charles Evans expressed concerns regarding weak inflation, which remains stubbornly below the central bank's 2 percent target. Both Kaplan and Evans are voting member on the Fed's rate-setting committee.
* However, Boston Fed head Eric Rosengren said that the era of low interest rates in the United States and elsewhere poses financial stability risks and that central bankers must factor such concerns into their decision-making.
* On the economic front, data is expected to show U.S. home resales dropped to 5.55 million from 5.57 million in May due to a chronic shortage in properties. The data is expected at 10 a.m. ET (1400 GMT).
* U.S. stocks closed lower on Tuesday, hurt by a sharp drop in oil prices while retail stocks were pulled down by concerns about Amazon.com's plan to boost its apparel business and a rebound in tech stocks petered out.
* The S&P technology sector, which helped the S&P 500 rally 8.85 percent this year, has been hit by concerns over valuation and investors' move into more defensive sectors.
* Adobe Systems was up 3.8 percent in premarket trading after the software forecast current-quarter above analysts' estimates.
* FedEx was up about 1 percent after the package delivery company reported a quarterly profit that beat analysts' estimates and forecast higher earnings for fiscal 2018.
* Red Hat jumped 10.5 percent to $99.40 after the Linux operating system distributor's second-quarter forecast came in above expectations, prompting a slew of price target lifts by brokerages.
Futures snapshot at 7:00 a.m. ET:
* Dow e-minis were up 4 points, or 0.02 percent, with 23,444 contracts changing hands.
* S&P 500 e-minis were down 2.5 points, or 0.1 percent, with 150,141 contracts traded.
* Nasdaq 100 e-minis were down 6.5 points, or 0.11 percent, on volume of 35,226 contracts. (Reporting by Sruthi Shankar in Bengaluru)