Semiconductor Stocks Surge on July 21 as Micron Jumps 12.17%, Volatility Hits 8% Daily Swings

According to Financial News, on July 21, major semiconductor stocks experienced extreme intraday volatility across global markets. Micron surged 12.17% to $970.82, while SanDisk (+14.24%), Intel (+8.64%), and AMD (+8.11%) also posted sharp gains on the New York Stock Exchange. In South Korea, Samsung Electronics and SK Hynix rose 4–6% on the Kospi.

This month, semiconductor stocks have shown unprecedented volatility, with Samsung Electronics, SK Hynix, Micron, AMD, and SanDisk recording an average intraday fluctuation rate of 7.99%—meaning stocks swung roughly 8% daily. SK Hynix led at 10.08%, while SanDisk reached 9.61%. By comparison, the Nasdaq Composite and S&P 500 averaged just 1.31% and 0.86% intraday volatility this month.