Stock index futures turned higher on Monday as positive quarterly results from companies including CVS Caremark Corp offset nagging worries about euro zone sovereign debt issues.

S&P 500 futures rose 2.2 points but were 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 19 points, while Nasdaq 100 futures were up 2.75 points.

(Reporting by Leah Schnurr)

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