Shares may have been likely to fall no matter what the company reported.By no means were Amgen's (AMGN -5.54%) second-quarter numbers "bad." Revenue for most of its core drugs was up year over year, and the slight earnings dip is the predictable result of rising expenses. The pharmaceutical company's outlook remains optimistic as well.Yet, S&P Global Market Intelligence data indicates Amgen shares are down 5.9% as of 12:46 p.m. ET today. The prompt for the sell-off is mostly an earnings miss, but the actual ...