Black Monday 1987
The 1987 crash that reshaped options markets and risk management forever.
Black Monday — October 19, 1987 — was the single largest one-day percentage drop in stock market history. The Dow Jones Industrial Average fell 22.6% in a single session, and the S&P 500 dropped 20.5%. In options terms, the move was a roughly 20+ standard deviation event — something the normal distribution would predict should happen less than once in the lifetime of the universe. The crash fundamentally changed how options are priced, hedged, and regulated.
Why It Matters
Black Monday is the most important historical event for options traders because it created the permanent volatility skew that defines options pricing today. Before 1987, options at different strikes were priced with roughly equal implied volatility. After the crash, out-of-the-money puts have been permanently more expensive relative to ATM options — the market prices in the possibility of another crash at all times.
The crash also demonstrated that theoretical models can fail catastrophically. Portfolio insurance — a strategy that dynamically hedged stock portfolios using futures — amplified the selling cascade. The lesson for options traders is that strategies that work in normal conditions can break down in ways that models do not predict.
How It Works
What happened:
- Markets had been rising sharply in 1987, gaining over 40% by August
- Concerns about trade deficits, rising interest rates, and overvaluation created anxiety
- On October 19, selling cascaded as portfolio insurance programs automatically sold futures
- The selling created a feedback loop: lower prices triggered more automated selling
- Market makers widened spreads dramatically or stopped quoting entirely
- Options became nearly impossible to trade as liquidity evaporated
Impact on options markets:
- Volatility skew was born: OTM puts became permanently more expensive relative to ATM options. Before 1987, the volatility "smile" was nearly flat. After 1987, it became a "smirk" — elevated on the downside.
- Options pricing changed: Models were updated to account for fat tails and jump risk
- Market maker behavior shifted: Market makers began pricing in crash risk and holding larger reserves
- Circuit breakers were introduced: Exchanges implemented trading halts to prevent cascading selloffs
Portfolio insurance failure: The strategy that amplified the crash worked by selling S&P 500 futures as the market fell, theoretically creating a synthetic put. The problem was that too many large institutions were using the same strategy simultaneously. When they all sold at once, futures dropped below the cash index by an unprecedented margin, and the "hedge" became the cause of further losses.
The options market aftermath: Many options market makers suffered catastrophic losses. Some firms failed. The OCC faced unprecedented stress but ultimately honored all contracts. The experience led to improved risk management, higher capital requirements for market makers, and a permanent change in how the industry thinks about tail risk.
Quick Example
A trader who sold 10 naked S&P 500 puts at the 280 strike (about 5% OTM) for $3.00 each on Friday, October 16, collected $3,000 in premium. On Monday, the S&P 500 dropped from 282 to 225. Those puts went from $3.00 to approximately $55 — a loss of $52,000 on a $3,000 trade. The margin system could not keep up, and many traders could not cover their losses.
The broader lesson: a position that appeared to be a comfortable 5% out of the money, with a modeled probability of profit above 90%, suffered a loss 17x the premium collected in a single day. This is the event that taught the options world to respect tail risk.