Wall Street edges up with Merck, IBM; Nasdaq slips with Apple

Apple kept trading volatile as it swung between gains and losses a day after reporting results. The stock hit a record high in early trading but shares were last down 1.5 percent at $130.63, weighing on the Nasdaq. Apple's numbers were phenomenal but yet the stock is down. U.S. first-quarter earnings are now on track to post a slight gain after stronger-than-expected results from companies such as Apple, defying forecasts for the first profit decline since 2009, Thomson Reuters data showed.