* Netflix surges 18 pct on strong subscriber growth
* UnitedHealth up on upbeat forecast, boosts health stocks
* CPI notches biggest gain in five months in September
* Indexes up: Dow 0.43 pct, S&P 0.62 pct, Nasdaq 1 pct (Adds details, comments, updates prices)
By Yashaswini Swamynathan
Oct 18 (Reuters) - The S&P and the Nasdaq were on track for their best day this month on Tuesday as a slew of market-beating results from marquee companies boosted optimism about Corporate America's health.
The spotlight was on the healthcare sector, which rose 1.04 percent, the most in more than one month, after UnitedHealth's upbeat forecast. UnitedHealth rose 6.3 percent and boosted its fellow health insurers.
Netflix, which dragged on the market on Monday ahead of its results, was the biggest gainer on the S&P 500 on Tuesday, rising nearly 19 percent after posting much higher-than-expected subscriber growth.
Goldman Sachs rose 2.2 percent, lifting shares of other banks, after the company's results blew past Wall Street estimates, mirroring results at its Wall Street peers.
Of the 37 S&P 500 companies that have reported results until Monday, 78 percent have reported earnings that have topped analysts average estimate, according to Thomson Reuters I/B/E/S.
Analysts now estimate earnings of S&P companies slipped 0.1 percent in the third quarter, less than their earlier estimate of a drop of 0.7 percent, raising hopes that a four-quarter streak of negative earnings growth could be snapped.
"We're seeing the delta improve to the upside in this earnings season and that sets the tone for the fourth quarter performance," said Terry Sandven, chief equity strategist at U.S. Bank Wealth Management in Minneapolis.
At 11:08 a.m. EDT (1508 GMT), the Dow Jones Industrial Average was up 77.49 points, or 0.43 percent, at 18,163.89.
The S&P 500 was up 13.21 points, or 0.62 percent, at 2,139.71 and the Nasdaq Composite was up 52.14 points, or 1 percent, at 5,251.97.
Even economic data helped boost sentiment. U.S. consumer prices recorded their biggest gain in five months in September, pointing to a steady build-up of inflation that could keep the Federal Reserve on track to raise interest rates in December.
"The economy continues to show signs of improvement, with the CPI data showing that there are signs of a modest level of inflation creeping into the marketplace," Sandven said.
Nine of the 11 major S&P 500 sectors were higher, with only the interest rate-sensitive utilities and telecom services in the red.
Among the laggards was IBM, which fell 3.3 percent after reporting its 18th straight quarter of revenue decline.
Johnson & Johnson was down 2.4 percent, while Pfizer gained 0.8 percent on after it announced plans to ship a cheaper biosimilar to Remicade, JNJ's top selling product. The news overshadowed J&J's slight earnings beat.
Intel, scheduled to report after markets close, rose 1.6 percent on a Barclays upgrade. Yahoo, also due to report in the evening, was up 0.7 percent.
Advancing issues outnumbered decliners on the NYSE by 2,199 to 656. On the Nasdaq, 1,797 issues rose and 788 fell.
The S&P 500 index showed three new 52-week highs and one new lows, while the Nasdaq recorded 32 new highs and 38 new lows. (Reporting by Yashaswini Swamynathan in Bengaluru; Editing by Savio D'Souza)