Wall St lower after CPI data; Yellen speech awaited

U.S. stocks fell in late morning trading on Friday, retreating from recent record highs, as investors await Federal Reserve Chair Janet Yellen's economic outlook for clues on the timing of a rate hike after new data showed a rise in inflation. Yellen is expected to highlight the economy's steady job growth, while April's consumer price index data is likely to bolster Fed's case for its first policy tightening in nearly a decade. Yellen's speech will start at 1:00 p.m. ET