Shares of International Business Machines Corp. tumbled 7.3% in midday trade Wednesday, in the wake of what is shaping up to be the most disappointing earnings report for investors in five years. IBM reported first-quarter earnings late-Tuesday that appeared to beat expectations--some questioned whether it was because of a one-time tax gain--and provided a somewhat downbeat outlook. IBM's results typically disappoint investors, as the stock has declined the day after earnings were reported in 16 of the past 20 quarters. However, Wednesday's selloff is on track to be the biggest one-day post-earnings since April 19, 2013, when the stock plunged 8.3% after first-quarter 2013 results. IBM shares have now lost 2.8% year to date, while the SPDR Technology Select Sector ETF has gained 6.2% and the Dow Jones Industrial Average has edged up 0.3%.