Fitch Ratings has cut its outlook for U.S. economic growth this year, but doesn't see slower growth deterring the Federal Reserve from raising interest rates. Fitch expects U.S. GDP to grow 1.8 percent in 2016, marking the first growth rate below two percent since 2013.  Fitch cites the decline in oil-related investment, due to the fact that oil prices were low in the first quarter, along with weakness in emerging markets which has impacted U.S. exports. Brian Coulton, Chief Economist at Fitch, says improvement in the U.S. labor market and expectations for higher inflation still warrant a boost in interest rates by the Fed in the second half of the year.  Coulton does not expect a rate hike in June. TheStreet's Rhonda Schaffler has details from Wall Street.