
Brian Duignan is a senior editor at Encyclopædia Britannica. His subject areas include philosophy, law, social science, politics, political theory, and religion.
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The dot-com boom of 1995â2000 (and ultimate bust in 2001â2002) was a period of large, rapid, and ultimately unsustainable increases in the stock marketâspecifically in the valuation of shares in Internet service and technology companies, then commonly referred to as âdot-comâ companies, including fledgling businesses, or âstart-ups,â with little or no record of profitability or with unrealistic business models.
During the dot-com bubble, the technology-dominated Nasdaq Composite index (a representation of the total value of the outstanding shares of companies listed on the Nasdaq stock exchange) rose nearly sevenfold from 743 to 5,048, reflecting the early enthusiasm of investors in dot-com enterprises and the willingness of venture capitalists to finance the initial public offerings (IPOs) of Internet start-ups, many of whose share prices then skyrocketed.
Indeed, many start-up employees who were initially compensated with stock options quickly became millionaires once their companies went public.
As the valuations of shares in new and existing dot-com companies continued to rise, many investors became convinced that the U.S. economy had been fundamentally transformed and that several factors that had traditionally figured in the valuation of a companyâs sharesâsuch as the assets and liabilities on its balance sheet, the revenue and profit on its income statement, as well as market share and cash flowâwere not directly relevant to assessing the future performance of dot-com companies, particularly start-ups. Accordingly, investors continued to pour money even into debt-ridden companies that had no realistic hope of ever turning a profit. Such investor overconfidence (often referred to as âirrational exuberance,â a phrase attributed to thenâFederal Reserve chair Alan Greenspan) led the shares of dot-com companies to be priced far in excess of the values that traditional assessment factors would have justified.
As do all financial bubbles, the dot-com bubble finally burst. In early 2000, after the U.S. Federal Reserve announced a modest increase in interest rates to stave off inflationary pressuresâa move that aimed to reduce investment capital by making borrowing more expensiveâinvestors in dot-com companies began a panicked sell-off of their holdings. Between March 2000 and October 2002, the Nasdaq fell from 5,048 to 1,139, erasing nearly all of its gains during the dot-com bubble. By the time the index bottomed out in October 2002, most publicly traded dot-com companies had failed.
This article was most recently revised and updated by Brian Duignan