The Trading Addict · Weekend Edition · Issue No. 105 · Saturday October 17, 2026

What's Happening
to Wall Street?

AI stocks took the hardest hit as the Nasdaq posted its worst week since June. Plus who we should believe on CoreWeave, October 19, 1987: the day Wall Street crashed, winners and losers, and Day 251 numbers.

The Trading Addict Newsletter · by Maria Helmick
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Rob Helmick, Maria Helmick & Nick Battista — Math Makes Money

The Trading Addict

Weekend Edition  •  Issue No. 105  •  Saturday October 17, 2026

In This Issue

What's Happening to Wall Street? — Nasdaq −2.14%, S&P 500 −1.09%, and the Nasdaq's worst week since June. Plus the calendar for October 19–23.  Jump to this story →
42 Capital Fund — Accredited investors: learn more about our fund.  Jump to this story →
Who Should We Believe? — CoreWeave's CEO vs. billionaire investor Chamath Palihapitiya: the debt, the business, and the influence behind Wall Street's reaction.  Jump to this story →
October 19, 1987 — The Day Wall Street Crashed — Black Monday: the Dow plunged 22.6% in a single day.  Jump to this story →
Trading With AI Bots · SPX 0-DTE — Bot access, live meetings, and 1,000 traders. Join the Math Makes Money Trading Team.  Jump to this story →
Today's Biggest Winners & Losers — S&P 500: TRGP, FANG, KMI up; SMCI, FLEX, MRNA down.  Jump to this story →
Day 251 · Fri Oct 16 Trading Update — $1M +$19,391 (120 tr) cum $701,269 (+70.13%). $30K +$859 (26 tr) cum $25,996 (+86.65%).  Jump to this story →
This Weekend's Show — Watch Rob and Nick on YouTube — live Mon-Fri 9:15 AM & 3:15 PM ET, plus Sunday 5:55 PM ET.  Jump to this story →
 
 
 
What's Happening to Wall Street? AI stocks take the hardest hit (tap to enlarge)
 
 
 
42 Capital Fund - Now accepting qualified investors. Click here.
 
 
 
Who Should We Believe? CoreWeave CEO Michael Intrator vs. Chamath Palihapitiya (tap to enlarge)
 
 
 
October 19, 1987: The Day Wall Street Crashed (tap to enlarge)
 
 
 
Trading With AI Bots, SPX 0-DTE. Click here to join the Math Makes Money Trading Team.

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Today's Biggest Winners and Losers, S&P 500, Oct 16 2026 (tap to enlarge)

» DAY 251 · FRI OCT 16 · DAILY TRADING UPDATE

Daily Trading Update Day 251 - Fri Oct 16 2026 - $1M +$19,391 (120 tr) cum $701,269 (+70.13%), $30K +$859 (26 tr) cum $25,996 (+86.65%)

Tap the dashboard to see the full summary online

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Rob and Maria Helmick and Nick Battista · The Trading Addict Newsletter

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Educational only. Not investment advice. Trading options involves substantial risk. Past performance does not guarantee future results.