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VST −5.8%: an unusually large move for this stock. Vistra Corp. moved 5.3 points less than its sector, on 1.3× its usual volume.

2026-10-08 · VST

VST −5.8%: an unusually large move for this stock

Vistra Corp. moved 5.3 points less than its sector, on 1.3× its usual volume.

The story in plain words

Thursday, October 8, 2026. VST −5.8%: an unusually large move for this stock. Vistra Corp. moved 5.3 points less than its sector, on 1.3× its usual volume.

What the data shows for Vistra Corp. (VST): VST −5.8% today. Its sector fund (XLU) −0.5% today. S&P 500 (SPY) −0.5% today.

Worked out from that data: 5.3 points less than its sector. Volume 1.3× its 20-day average. Bigger than 95% of its daily moves over the past 250 trading days.

Possible contributors. These line up in time with the move; they are not confirmed causes: News: “Stocks Sink After OpenAI Report Sours AI Trade” (Published around the move. Timing only, not a confirmed cause). News: “Stay informed with the top movers within the S&P500 index on Thursday.” (Published around the move. Timing only, not a confirmed cause). 144 filed (Filed around the move. Timing only). 144 filed (Filed around the move. Timing only).

About the company: Vistra Corp. trades as VST and is part of the S&P 500, in the Utilities sector (Electric Utilities), headquartered in Irving, Texas, founded in 2016.

This is one of CookieStocks’ daily stock stories about unusually large one-day price moves in S&P 500 stocks, measured against each stock’s own history, its sector and its usual volume. Stories are found automatically each trading day from market data and SEC filings, and every claim is labelled as observed, calculated or a possible contributor. Statistics only, not investment advice.

Prove it

Every claim on the graphic, labelled: observed (straight from the data), calculated (worked out from it), or possible contributor (lines up in time, not a confirmed cause).

  • OBSERVED
    VST −5.8% todayOct 8, 2026, 2:35 PM ET
  • OBSERVED
    Its sector fund (XLU) −0.5% todayOct 8, 2026, 2:35 PM ET
  • CALCULATED
    5.3 points less than its sectorHow: stock return − sector fund return · Oct 8, 2026, 2:35 PM ET
  • OBSERVED
    S&P 500 (SPY) −0.5% todayOct 8, 2026, 2:35 PM ET
  • CALCULATED
    Volume 1.3× its 20-day averageHow: today’s volume ÷ average of the last 20 days · Oct 8, 2026, 2:35 PM ET
  • CALCULATED
    Bigger than 95% of its daily moves over the past 250 trading daysHow: share of past daily moves smaller in size · Oct 8, 2026, 2:35 PM ET
  • POSSIBLE CONTRIBUTOR
    News: “Stocks Sink After OpenAI Report Sours AI Trade”Published around the move. Timing only, not a confirmed cause. · Oct 8, 2026, 1:35 PM ET
  • POSSIBLE CONTRIBUTOR
    News: “Stay informed with the top movers within the S&P500 index on Thursday.”Published around the move. Timing only, not a confirmed cause. · Oct 8, 2026, 12:35 PM ET
  • POSSIBLE CONTRIBUTOR
    144 filedFiled around the move. Timing only. · Source: SEC EDGAR · Oct 7, 2026, 4:00 PM ET
  • POSSIBLE CONTRIBUTOR
    144 filedFiled around the move. Timing only. · Source: SEC EDGAR · Oct 6, 2026, 4:00 PM ET

Vistra Corp. (VST) financials and filings →

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Statistics only, not investment advice. Past moves don’t predict future ones. Data as of Oct 8, 2026, 2:35 PM ET.