Investors may wade into unknown territory next month as the Federal Reserve readies the first rate hike in nearly a decade amid a corporate earnings recession. S&P 500 earnings are on track to close their first reporting season of negative growth since the Great Recession and estimates call for sub-zero growth in the current quarter as well. “We can’t think of any instances when the Fed was hiking during an (earnings) recession,” said Joseph Zidle, portfolio strategist at Richard Bernstein Advisors in New York.