A sharp technology-led sell-off has produced very different pictures across major US market benchmarks. The broad S&P 500 remained 6% below its October 6 record after its worst daily fall in more than a year, while the Nasdaq and semiconductor shares had suffered substantially deeper declines.
The S&P 500 dropped 4.4% on November 5, its steepest one-day retreat since April 2025, according to the market data summarized in the supplied analysis. That move attracted comparisons with famous crashes, but the index's total decline from its record remained modest next to the major bear markets of 1987, 2008 and the early months of the Covid-19 pandemic.
Historical data in the analysis show that a 6% retreat does not, by itself, predict a severe crash. Of 56 S&P 500 declines of at least 6% from a record since 1928, 30 ended before reaching 10%. The comparison is descriptive rather than a forecast: past episodes vary in their causes, speed and recovery, and the present decline could still change direction.
The pressure has been much more concentrated in technology. The Nasdaq was 11% below its record, while the PHLX Semiconductor Index had fallen 36% from its June 22 peak. That chip-stock decline was approximately as deep as the sector's 35% fall during the Covid shock, even though the broader S&P 500 had not experienced anything comparable.
The divergence matters because broad-index headlines can conceal the scale of losses within a heavily exposed industry. Semiconductor companies became central to the artificial-intelligence investment boom by supplying the processors, networking equipment and manufacturing capacity behind new computing infrastructure. A reassessment of expected growth or valuations can therefore hit those shares harder than the rest of the market.
The historical charts use price returns from a record close to the low that followed. They do not include dividends, which would shorten some measured recovery periods for a long-term investor who reinvested payouts. They also depict the outcome for an investor buying at the prior peak, not the experience of every market participant.
As of the event date, the evidence supports describing the broad-market move as a correction rather than placing it alongside the deepest US crashes. The semiconductor decline is the notable exception in scale. Further daily data will determine whether weakness remains concentrated in AI-linked shares or spreads more broadly. For now, the figures show both real stress in chips and a considerably smaller drawdown across the wider market.
