Amazon erased $68.1 billion in market capitalization Friday after the company fell short of Wall Street's revenue expectations in the third quarter, making software giant Microsoft the second-largest company in the United States.

Jeff Bezos' mammoth e-commerce company plunged 7.8 percent on the week's final day of trading, the stock's worst day since Oct. 24, 2014. Amazon's market cap is now $803.28 billion; Bezos himself lost $11 billion in equity value Friday.

Google-parent Alphabet, which also missed revenue expectations on Thursday, fell 1.8 percent Friday. The move reduces its market cap by $15.29 billion.