The VIX Futures Curve as an Indicator of Market Stress Regimes

1. Background & Objectives

The objective was straightforward: determine whether the VIX futures curve adds practical value as an indicator of changing market risk.

The analysis was not designed to forecast the exact future path of SPY. Instead, it focused on a structural question: has the volatility market moved from a normal state into a regime where short-dated protection is priced more aggressively than longer-dated protection?

The dataset combined Cboe data for VIX Spot and monthly VX futures with local SPY price data. The review covers 2017-01-03 through 2026-07-24, representing 2,403 trading sessions.

2. Contango & Backwardation

In a normal and relatively calm market environment, the VIX futures curve is usually in contango, meaning longer-dated futures trade above shorter-dated futures:

VX1 < VX2 < VX3

Backwardation is the opposite condition, where near-term futures trade above longer-dated futures:

VX1 > VX2 or VX2 > VX3

This typically occurs when demand for immediate protection rises sharply, often during periods of elevated fear, market stress or rapid equity declines.

3. Methodology

• A Curve Stress Score was developed on a scale of 0–100.
• The score was based on three spreads: SPOT→VX1, VX1→VX2 and VX2→VX3.
• Readings above 50 were tested as indications of elevated stress.
• The analysis examined whether these signals appeared ahead of meaningful SPY drawdowns or prolonged periods of weakness.
• A confirmation layer was later added, requiring SPY to trade below its 20-day moving average.

4. Key Findings

The original signal successfully identified several major stress periods, including February 2018, the fourth quarter of 2018, the 2020 COVID shock, significant parts of 2022 and the August 2024 volatility event.

However, it did not perform as a clean standalone downside signal. In many cases, the reading increased only after market stress had already begun. In others, the equity market recovered quickly without developing into a sustained drawdown.

5. Model Refinement

The main source of noise occurred when VIX Spot moved above VX1 while the futures curve itself remained in contango. This reflected front-end pressure, but not a genuine inversion of the VX futures curve.

Under the original definition, these conditions could still push the score above 50. This produced 17 false-positive entries out of 82, or 20.7% of all entries. On a daily basis, there were 25 false-positive days out of 403 days above 50, equivalent to 6.2%.

The condition SPOT > VX1 was retained, but moved into a separate category: SPOT_PRESSURE. It is no longer treated as a full market-stress signal.

6. Structural + Technical Filter

The next stage combined the VIX curve signal with a basic technical condition in SPY:

RISK_OFF_CONFIRMED = Curve Score ≥ 70 + Futures Backwardation + SPY below MA20

7. Signal Evaluation

An unconfirmed signal was defined as a RISK_OFF_CONFIRMED reading that was not followed by a drawdown of at least 5% in SPY within 60 trading days.

Using a stricter 10% drawdown threshold, the proportion of unconfirmed signals increased to 62.5%. The indicator therefore does not provide a sufficiently robust basis for standalone trading decisions. A 52.1% confirmation rate is too close to chance to justify using the signal by itself for market timing.

8. Conclusions

The indicator is effective at identifying structural changes in the volatility regime, but it does not demonstrate sufficient predictive strength for forecasting SPY drawdowns on a standalone basis.

Its value lies in regime identification: recognizing when the volatility market has shifted from a normal environment to a stressed one. Its limitation lies in converting that regime change into a consistently tradable downside event. Of the 48 RISK_OFF_CONFIRMED signals tested, only 25 were followed by a drawdown of at least 5% within 60 trading days.

9. Methodological Note

This analysis is based on historical data and is provided for informational and research purposes only. It does not constitute investment advice, a recommendation to buy or sell any security, or a guarantee of future performance.