Amazon CEO Andy Jassy speaks during the GeekWire Summit in Seattle on Oct. 5, 2021. Amazon shares slid more than 3% in extended trading on Thursday after the company reported second-quarter results that exceeded expectations, but it gave light operating income guidance for the current period. Here's how the company did, compared with estimates from analysts polled by LSEG: Earnings per share: $1.68 vs. $1.33 estimated $1.68 vs. $1.33 estimated Revenue: $167.7 billion vs. $162.09 billion estimated Wall Street is also looking at other key revenue numbers: Amazon Web Services: $30.87 billion vs. $30.8 billion estimated, according to StreetAccount $30.87 billion vs. $30.8 billion estimated, according to StreetAccount Advertising: $15.7 billion vs. $14.9 billion estimated, according to StreetAccount Amazon's second-quarter sales grew 13% year over year to $167.7 billion, an acceleration from a year ago, when revenue expanded 10%. For the current quarter, Amazon said it expects operating income to land between $15.5 billion and $20.5 billion. Analysts were looking for $19.48 billion, according to StreetAccount. The guidance spooked investors who are eager to see Amazon's hefty investments in artificial intelligence pay off. The company has committed to spend up to $100 billion this year on AI as it races to build out infrastructure and software. "Our AI progress across the board continues to improve our customer experiences, speed of innovation, operational efficiency, and business growth, and I'm excited for what lies ahead," Amazon CEO Andy Jassy said in the earnings release.