Shares of Dexcom fell 9% in extended trading on Thursday after the company released third-quarter results that beat analysts' expectations but showed a decline in U.S. revenue year over year.Here's how the company did:Earnings per share: 45 cents adjusted vs. 43 cents expected by LSEGRevenue:  $994 million vs. $990 million expected by LSEGThe company's revenue increased 2% to $994.2 million from $975 million a year earlier. Dexcom's U.S. revenue declined 2% from $713.6 million the prior year. The company re ...