The plunge in Amazon.com Inc.’s stock          AMZN,         -9.31%        following a disappointing third-quarter earnings report and outlook puts the ecommerce giant on track to lose its place as a trillion-dollar company for the first time in 2 1/2 years. The stock dropped 12.0% in premarket trading, and is heading for the first trade below the $100 level during regular-session hours since April 7, 2020. With 10.202 billion shares outstanding as of Oct. 19, the implied price decline would erase about $135.4 billion in market capitalization, to knock the total market down to about $996.6 billion. The last time Amazon closed below the $1 trillion market-cap line was April 6, 2020. That would leave just three $1+ trillion market cap companies: Apple Inc.          AAPL,         +4.72%,        which had a market cap of $2.33 trillion as of Thursday’s close; Microsoft Corp.          MSFT,         +1.39%        at $1.69 trillion; and Alphabet Inc.          GOOGL,         +1.07%         GOOG,         +0.75%        at $1.19 trillion. Amazon’s stock selloff comes as futures          ES00,         +0.18%        for the S&P 500          SPX,         +0.80%        declined 0.6%, while futures          NQ00,         +0.15%        for the technology-heavy Nasdaq 100          NDX,         +1.06%        shed 0.9%.