Investors will rake in more than $1 trillion in 2015 as U.S. companies increase stock buybacks and boost dividends, Goldman Sachs Group Inc said, with benefits coming soon as many S&P 500 companies exit a blackout period for repurchases next week. “Corporate activity in early 2015 supports our view that the S&P 500 will return more than $1 trillion of cash to investors this year,” said David Kostin, chief U.S. equity strategist at Goldman in New York said in an April 24 note to clients.