Why Did IBM Stock Tumble After an Earnings Beat?

Shares of International Business Machines (IBM -6.62%) dropped like a rock on Thursday despite reporting first-quarter results Wednesday evening that beat analyst expectations across the board. Revenue of $14.5 billion was up 2% at constant-currency measures, and non-GAAP earnings per share came in at$ 1.60. While earnings did decline, analysts were expecting worse. On top of beating analyst estimates, IBM maintained its full-year guidance for revenue growth and free cash flow.Despite a solid earnings repor ...