Micron Stock Has Moved 5% or More on a Third of Its Trading Days Since October. Here's How Much of It I'd Own.

Micron Technology's stock has shown significant volatility since October, swinging 5% or more on roughly a third of its trading days during that period. The stock fell 17.5% on November 5, before recovering 24% over the next four sessions. As of the latest data, shares are near $811, having lost nearly a quarter since the end of September.

Six of the 10 substantial swings were declines, occurring on October 16, 22, 30, November 2, 4, and 5. The four gains were on October 28, November 6, 9, and 11. Eight of the 10 big swings happened within 11 trading days from October 28 to November 11.

Over the five trading days ending November 5, Micron's shares dropped by about 30%, with a $100,000 portfolio with 10% in Micron shrinking to roughly $7,000, a 3% loss for the entire portfolio. A 5% weight would result in a 1.5% hit, while a 25% weight would mean a 7.4% drop. The worst-case scenario saw Micron's stock fall 54% from its June 2018 record close to its November 2022 low, even as the company's profits kept increasing.

Micron's fiscal 2026 fourth quarter saw revenue of $54.2 billion, up 380% year over year, and both net income and earnings per share grew over elevenfold year over year. Gross margins reached 87%, up from 85% in Q3 and 46% a year earlier. Management guidance for fiscal Q1 forecasts revenue of around $61.5 billion and an adjusted gross margin of about 86%.

Despite the high gross margins, Micron's stock can experience sharp swings based on hints about memory prices. The current price already accounts for potential profit drops. However, this also means the stock's future is influenced by guesses about the boom's longevity, which can shift week to week. A prudent approach is to size Micron so that a 50% drop would only cost about 2.5% of a diversified portfolio, roughly 5% at most.