Amazon became the second company to reach a US$1 trillion market capitalization after Apple in 2018.
Amazon crossed the threshold on September 4, 2018, about one month after Apple reached it. Investors had rewarded Amazon for its rapid expansion from online retail into cloud computing, digital advertising, logistics, and subscription services.
Amazon Web Services became especially important to the company’s financial profile. Although Amazon began as an online bookseller, its cloud division grew into one of the world’s largest providers of computing infrastructure.
The phrase “valuation” here means stock-market capitalization, not a private-company estimate. Amazon’s market cap was calculated from its publicly traded shares, and the exact figure moved as the stock price changed during the session.