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Oct 19, 1987

Black Monday

The single worst day in stock market history. The Dow plunged 22.6% — 508 points — in a single session. Program trading amplified the panic.

-22.6%DJIA in one day

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Aug 20, 1987Black MondayDec 18, 1987
±60 trading days around the event

S&P 500 Around This Event

GSPC.INDX · ±60 days
Aug 20Aug 25Aug 31Sep 4Sep 11Sep 17Sep 23Sep 29Oct 2Oct 7Oct 13Oct 19Oct 23Oct 28Nov 3Nov 8Nov 12Nov 18Nov 24Dec 1Dec 6Dec 10Dec 18$210$245$280$315$350
GSPC.INDX Intraday Trading Activity

Open

$149.22

Close

$154.02

High

$158.27

Low

$148.71

Daily Change
+4.80 (3.22%)
$148$151$154$1590M0M0M0M0M09:3010:0010:3011:0011:30
  • volumeM
  • high
  • close
09:30 — 11:55•30 of 78 candles
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Key Market Events

09:30 — Market Open
16:00 — Market Close

Circuit Breaker Levels

-7% Halt
-13% Halt
-20% Halt (Close for day)

Event Day Price

$224.84

Period High

$336.77

Period Low

$223.92

Period Change

-25.6%

What Happened Next?

1 Week Later

+15.2%

1 Year Later

+23.0%

Key Takeaway

Markets recovered within 2 years

“It’s human nature to do things in groups. This is extreme in markets. I’ve seen first hand large allocators who, as an organisation, seem to prefer losing money in a conventional way, than making money by themselves.”

“The market isn’t efficient or inefficient. That’s too simple. To me it’s just a thing, made up of players each of whom have different goals, different time horizons and different strategies.”

DS

David Steinberg

Founder, Marlowe

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Historical data for educational purposes only. Not financial advice.