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• Fed edges toward first rate hike since 2006
The Conference Board's index of consumer attitudes dropped to 90.9 in July, down from a downwardly revised 99.8 in June. It was the weakest reading in 10 months. To be sure, analysts suggested the weakness might be short-lived.
"This seems to be an aberration,"Ryan Sweet, senior economist at Moody's Analytics in West Chester, Pennsylvania, told Reuters. "Consumers were probably freaked out by the problems in Greece and the Chinese stock market, and the volatility on Wall Street."
Separately, the S&P/Case Shiller composite home price index of 20 metropolitan areas rose 4.9 percent from May 2014, following a 5 percent increase in the year ended in April.
The data shows "a housing market that's growing quite healthily but isn't overheating," David Sloan, a senior economist at 4Cast in New York, told Bloomberg. That's "probably a fairly good picture as far as the Fed is concerned."
Shares of United Parcel Service gained, last up 5.5 percent, after the bellwether company reported stronger-than-expected earnings and an optimistic outlook.
"The strong momentum in our international segment is expected to continue and gives us confidence in achieving the upper end of our guidance range," UPS chief executive officer David Abney said in a statement.
Shares of Pfizer climbed, last up 2.7 percent, after the company posted quarterly profit that exceeded estimates.
Shares of SuperValu soared, last up 16.5 percent, after the company reported its latest earnings and said it is exploring a spinoff of its Save-A-Lot business, potentially into a stand-alone, publicly traded company.
Fresh M&A activity also buoyed the mood. Shares of Honeywell International advanced, last up 2.7 percent, after the company agreed to buy Britain's Melrose Industries for about US$5.1 billion.
In Europe, the Stoxx 600 Index finished the session with a 1.1 percent increase from the previous close. The UK's FTSE 100 Index added 0.8 percent, France's CAC 40 advanced 1 percent, while Germany's DAX rallied 1.1 percent.