By John S. McClenahen Between January and March, U.S. employment costs increased 1.1% -- and are up 4.1% from the comparable period last year. Wages and salaries rose 1%, while benefits, the other component of the U.S. Labor Dept.'s Employment Cost Index, rose 1.3%. But Stan Shipley, a senior economist at Merrill Lynch & Co., New York, terms the wage and salary number "non-threatening." And Maury Harris, economist at UBS Warburg, notes that the wage figure is actually down from its recent peak. "As a result," says Harris, "this report should tend to lessen inflation fears relative to average hourly earnings." Indeed, Shipley expects the inflation-wary Federal Open Market Committee (FOMC) to lower the influential federal funds rate by another 50 basis points -- to 4% -- at its May 15 meeting. Harris seconds that prediction-and is betting the FOMC will make another 50-basis-point cut -- to 3.5% -- at its late-June get-together.