Zero-Day Options: What Overnight Moves Signal

Zero Day Option Trading & Overnight Market Moves: A Detailed Analysis

Key Concepts:

Zero Day Options (Zero DTE): Options contracts expiring on the same day they are traded.
Iron Condor: A neutral options strategy involving the sale of an out-of-the-money call spread and an out-of-the-money put spread.
Delta: A measure of an option's sensitivity to changes in the underlying asset's price. (e.g., 40 Delta, 20 Delta)
Overnight Gap: The difference in price between the closing price of an asset on one day and its opening price on the next.
Realized Volatility: The actual volatility of an asset over a given period.
Synthetic Straddle: An options strategy that mimics the payoff profile of a straddle, often created with wider option spreads.
VIX: The CBOE Volatility Index, a measure of market expectations of near-term volatility. (18 VIX represents a ~1% daily move)

I. Introduction & Study Overview

The discussion centers on analyzing the impact of overnight market movements on the performance of zero-day-to-expiration (Zero DTE) options trading strategies, specifically iron condors. The core question is whether filtering trades based on the magnitude and direction of overnight S&P 500 moves can improve strategy performance. The study utilizes three years of data, collecting zero-day option data every 10 minutes, focusing on trades placed around 9:00 AM.

II. Methodology & Data Parameters

The research employs a systematic approach to categorize overnight S&P 500 moves and assess their influence on zero-day option profitability. Key parameters include:

Data Source: Three years of zero-day option data for the S&P 500.
Trade Structure: Short strikes at either the 40 or 20 delta, long strikes at 10, 20, and 30 delta. Trades are closed when they reach 20% of their maximum profit.
Overnight Move Categorization:
- Large Move: Greater than 0.5% in either direction (considered beyond typical 18 VIX daily move).
- Small Move: 0.2% to 0.5% in either direction.
- Flat Move: Within 0.2% in either direction.
Wing Widths: Analysis conducted with 10-point, 20-point, and 30-point wide wings.

III. Results: Impact of Overnight Moves on 40 Delta Shorts (10-Point Wide)

The initial analysis focuses on 40 delta short options with 10-point wide wings. The findings indicate:

Small Overnight Moves are Optimal: Trades initiated after small overnight moves demonstrate the best performance.
Large Up Moves are Profitable: Large overnight up moves also yield strong profits, potentially due to a "chopfest" pattern where the market rallies overnight and remains relatively stable throughout the day.
Large Down Moves are Neutral: Large overnight down moves show performance comparable to flat overnight moves.
Context of the Market: The three-year data set reflects a generally bullish market, influencing the observed results.

As stated, “you’re seeing the big difference between the large down day and the large upday…the large update, you’re getting that realized volatility in the overnight session and then like nothing is happening throughout the the the day.”

IV. Results: Impact of Wing Width on Performance

Expanding the wing width to 20 points and 30 points reveals:

Diminishing Returns: Increasing the wing width does not significantly improve profitability. Win rates may increase, but the potential for larger losses offsets these gains.
Increased Risk: Wider wings introduce greater tail risk and maximum loss potential.
Consistent P&L: Average P&L remains relatively consistent across 10, 20, and 30-point wide wings, suggesting that widening the wings doesn't provide a substantial advantage.

The analysis highlights that, "you're adding a lot more risk on these trades specifically…the rate of change of these P&L wise is going to be even lesser because you you have a lot more tail risk."

V. Results: Impact of 20 Delta Shorts

Shifting to 20 delta short options demonstrates:

Positive P&L Across the Board: Positive P&L is observed across all overnight move categories.
Best Performance: Flat and large up moves continue to show the best results.
Large Down Moves Benefit: Large down moves show improved performance compared to the 40 delta analysis, likely due to the position being further out-of-the-money and benefiting from realized volatility.
Quick Management is Key: The data reinforces the importance of quick trade management (closing at 20% max profit) for maximizing profitability.

VI. Key Takeaways & Recommendations

The study concludes with several key takeaways:

Zero DTE Trading Remains Viable: Over the past three years, there hasn't been a consistently bad time to sell delta-neutral iron condors in zero-day options.
Avoid Small Up Moves: Small overnight up moves consistently underperform.
Capitalize on Large Up Moves: Large overnight up moves often lead to strong zero-day profits.
Strike Selection Matters: The 20 delta short option generally offers a more balanced risk-reward profile compared to the 40 delta.
Quick Management is Crucial: Closing trades at 20% of maximum profit is a key component of success.
Flexibility is Important: Zero-day trading is adaptable and can be applied daily.

As stated, "managing these quickly is probably the overall best thing to do with these sort of trades is just manage them quickly, get out, take your money, and run."

VII. Conclusion

This research provides valuable insights into the relationship between overnight market movements and zero-day option trading performance. The findings suggest that traders can potentially improve their results by filtering trades based on the magnitude and direction of overnight S&P 500 moves, with a particular focus on avoiding small up moves and capitalizing on large up moves. The emphasis on quick trade management and the benefits of using 20 delta short options further refine the strategy. The study acknowledges the limitations of a three-year data set and the influence of a bullish market environment, suggesting that future research may be needed to validate these findings across different market conditions.