* S&P 500 has ended higher 13 times in the past 16 sessions
* Amazon, Zynga shares pressured in premarket after results
* Vivendi overhaul gathers pace with $8.2 bln Activision deal
* Futures down: S&P 8.3 pts; Dow 63 pts; Nasdaq 5.5 pts
By Angela Moon
NEW YORK, July 26 (Reuters) - Wall Street was set for a lower open on Friday as the market took a breather from a recent rally that has taken the S&P 500 up 18.5 percent for the year and as investors digested a slew of major earnings.
Major U.S. stock indexes have advanced steadily this year with the S&P 500 hitting an all-time high earlier this week. The broad market index has ended higher 13 times in the past 16 sessions. For July, the benchmark has added 5.2 percent.
"As investors absorb many earnings reports this morning, they are also questioning, 'Can we get through the 1,700 (on the S&P 500)? Can we get a push beyond this round number?'" said Andre Bakhos, director of market analytics at Lek Securities in New York.
"I still think the short-term weakness will just provide more buying opportunities for investors that have missed the boat."
In economic news, the ThomsonReuters/University of Michigan's consumer sentiment index is due at 9:55 a.m. ET.
S&P 500 futures fell 8.3 points and 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 fell 63 points, and Nasdaq 100 futures lost 5.5 points.
On Thursday, the S&P 500 added 4.31 points, or 0.26 percent, to end at 1,690.25.
In earnings, Starbucks Inc shares rose 7 percent to $72.94 in premarket trade, a day after the world's biggest coffee chain posted a bigger-than-expected jump in quarterly profit.
Falling shares included Amazon.com Inc, which lost 1.7 percent to $298.23 in premarket trade after the company's forecast disappointed on income and revenue. Amazon.com is faced with a weaker international market, overshadowing improved profit and economic conditions in the United States.
Zynga Inc shares plunged 17.4 percent in premarket trade a day after the company announced it will largely abandon its efforts to build an online gaming business in the United States.
Online travel agency Expedia Inc shares plunged 23 percent to $50.20 a day after the company reported a quarterly profit far short of market estimates due to higher competition and poor performance in its discount website, Hotwire.com.
As of Thursday's close, 47 percent of the S&P 500 companies reported earnings, and about 68 percent of them have topped profit forecasts, above the historical average of 63 percent. About 56 percent have reported better-than-expected revenue, a rate that is below the historical average.
In M&A news, Vivendi plans to sell the bulk of its stake in Activision Blizzard Inc to the video games maker and its management for $8.2 billion, the French conglomerate's second blockbuster deal in a week.
Activision shares, one of the most traded in premarket, jumped 16.6 percent to $17.72.
European shares edged lower on Friday. Germany's DAX market had already unsettled some investors this week with profit warnings from some of its leading companies.
In Asia, Japan's Nikkei share average slid 3 percent and was near a three-week low on Friday, with blue-chip exporters and financials leading declines on the back of a stronger yen and profit-taking.