What Happens When Markets Crash? How ETFs Behave During Major Downturns

Crashes Are Not Anomalies

Severe market downturns are not rare events. They are a recurring feature of equity markets. In the past two decades alone, investors have experienced three distinct types of major selloffs: the 2008 financial crisis (slow-building, systemic), the 2020 pandemic crash (sudden, sharp, fast recovery), and the 2022 bear market (grinding, rate-driven, prolonged).

Each of these events tested investment strategies differently. Understanding how various ETF approaches performed during each provides practical insight into what actually works when markets are under stress, not what backtests suggest should work.

The 2008 Financial Crisis

The 2008 crisis was the most severe equity market downturn since the Great Depression. The S&P 500 Index fell approximately 57% from its October 2007 peak to its March 2009 trough. The decline unfolded over 17 months, with periodic rallies that gave false hope before further legs down.

What happened to defensive strategies:

• Low-volatility stocks: Companies with low historical volatility declined less than the broad market, but the losses were still severe. Estimates suggest the lowest-volatility quintile of stocks lost roughly 35 to 40%, significantly less than 57% but still devastating for clients who expected "low volatility" to mean "safe."
• Utilities: The utilities sector fell approximately 35% from peak to trough. This was better than the broad market but still a major loss for a sector marketed as defensive.
• Consumer staples: The consumer staples sector declined roughly 25 to 30%. Again, better on a relative basis, but the absolute loss was substantial.
• Bonds: Investment-grade bonds were one of the few asset classes that held up, with the Bloomberg Aggregate gaining ground during 2008. But even bonds experienced sharp volatility during the Lehman Brothers collapse in September 2008.
• Cash: Money market funds and Treasury bills preserved capital entirely, with the notable exception of one money market fund that "broke the buck" due to Lehman exposure.

The key lesson: Every equity-based strategy, regardless of methodology, suffered significant losses. The distinction between a 35% loss and a 57% loss matters, but neither outcome is acceptable for a client who needs capital preservation. The only strategies that avoided losses entirely were those that moved out of equities before or during the early stages of the decline.

The March 2020 Pandemic Crash

The pandemic selloff was remarkable for its speed. The S&P 500 fell 34% in just 23 trading days, from February 19 to March 23, 2020. It was the fastest bear market in history. It was also followed by one of the fastest recoveries, with the index reclaiming its highs by August.

What happened to defensive strategies:

• Low-volatility ETFs: Major low-vol products fell roughly 25 to 30% during the crash, less than the broad market but still punishing. The speed of the decline meant that most rebalancing mechanisms did not trigger quickly enough to provide meaningful mitigation.
• Minimum volatility factor ETFs: The iShares MSCI USA Min Vol Factor ETF declined approximately 27% from its pre-pandemic peak to the March trough. The optimizer's diversification benefit was overwhelmed by the universal selling pressure.
• Defensive sector ETFs: Utilities fell roughly 30%. Consumer staples fell roughly 20%. Healthcare held up relatively better but still declined about 15 to 20%.
• Bonds: Intermediate-term bonds experienced a brief but sharp selloff in mid-March 2020 as liquidity evaporated. Even Treasury bonds, the traditional safe haven, saw unusual volatility. The 60/40 portfolio did not provide the expected cushion during the initial days of the crash.
• Cash: Money market instruments held their value completely. Federal funds rate was near zero, so the return was negligible, but capital was preserved entirely.

The speed problem: The 2020 crash exposed a critical weakness in calendar-based rebalancing. Products that adjust quarterly or semi-annually could not respond to a selloff that unfolded over three weeks. By the time the next scheduled rebalance arrived, the market had already begun recovering. Strategies that use signal-driven, real-time adjustment had a structural advantage here: they could respond as conditions changed, not on a pre-set schedule.

The recovery trap: The V-shaped recovery created its own challenge. Strategies that successfully moved to cash during the crash needed to move back to equities quickly to capture the rebound. Systematic approaches with clear re-entry signals had an advantage over discretionary managers who were still debating whether the bottom was in.

The 2022 Bear Market

The 2022 decline was fundamentally different from 2008 and 2020. It was driven by Federal Reserve rate hikes, not a financial crisis or an exogenous shock. The S&P 500 fell roughly 25% from January to October 2022, but the decline was grinding rather than sudden, with multiple bear market rallies along the way.

More importantly, 2022 broke the 60/40 framework. Bonds, which had historically cushioned equity losses, fell alongside stocks. The Bloomberg Aggregate Bond Index lost approximately 13% in 2022, its worst year in decades. For advisors relying on bonds to offset equity risk, the traditional playbook failed.

What happened to defensive strategies:

• Low-volatility ETFs: The Invesco S&P 500 Low Volatility ETF declined approximately 6% in 2022, significantly outperforming the S&P 500. However, its heavy weight in utilities became a liability as rates rose, and the fund underperformed expectations for a "defensive" allocation.
• Minimum volatility factor ETFs: The iShares MSCI USA Min Vol Factor ETF fell approximately 11% in 2022. Better than the broad market, but the rate sensitivity embedded in its sector weights was visible.
• Defensive sectors: The performance was mixed. Energy surged (benefiting from the inflation that was driving rate hikes). Utilities were flat to slightly negative as their rate sensitivity offset their defensive characteristics. Healthcare outperformed. Consumer staples were modestly down.
• Bonds: Failed as a diversifier. Every type of fixed income lost value. Long-duration bonds were hit hardest, but even short-term bonds posted negative returns.
• Cash: Initially returned near zero (rates started the year near 0%). As the Fed raised rates throughout the year, money market yields rose above 4%. By the end of 2022, cash was yielding more than many bond funds while having experienced zero capital loss.

The 2022 lesson for advisors: The assumption that bonds protect during equity downturns is not always valid. When inflation and rate hikes drive the decline, bonds and stocks can fall together. Cash, or the ability to rotate to cash, becomes the only reliable capital preservation tool in that environment.

What Would a Cash-Rotation Strategy Have Done?

Consider what a systematic signal-based strategy with the ability to rotate to 100% cash would have experienced during each event:

2008: A strategy monitoring trend and momentum signals would have begun reducing equity exposure in late 2007 or early 2008 as multiple indicators deteriorated. By the time Lehman Brothers collapsed in September 2008, a signal-driven approach would likely have been substantially or entirely in cash. The exact timing depends on the specific signal thresholds, but the direction is clear: signals were deteriorating for months before the worst of the crisis.

2020: The speed of the pandemic crash was a challenge for any strategy. However, volatility signals spiked rapidly in late February 2020, and a responsive system could have begun reducing exposure within days. The full 34% decline would not have been avoided, but a meaningful portion of it could have been mitigated. More importantly, a systematic re-entry process would have moved back into equities as signals improved, capturing much of the subsequent recovery.

2022: The grinding nature of the 2022 decline was actually favorable for signal-based approaches. The deterioration was gradual, giving systematic models time to adjust. A strategy that rotated to cash as trend and momentum signals weakened would have avoided much of the loss while earning rising money market yields as the Fed hiked rates. The portfolio would have been earning 4%+ in cash while equities were falling 25%.

The Compounding Effect of Avoiding Large Losses

The mathematics of drawdowns are asymmetric. A 50% loss requires a 100% gain to recover. A 30% loss requires a 43% gain. A 20% loss requires a 25% gain. The larger the loss, the more disproportionate the recovery requirement.

This is why downside mitigation is not just about comfort; it is about math. A portfolio that avoids a significant portion of a major drawdown needs a much smaller recovery to return to its prior level. Over multiple market cycles, this compounding advantage can be substantial.

Consider a simplified illustration: Portfolio A stays fully invested and experiences a 40% decline, requiring a 67% gain to recover. Portfolio B, using signal-based cash rotation, experiences a 15% decline during the same period. It needs only an 18% gain to recover. When the market eventually rebounds, Portfolio B returns to its starting point far sooner and can compound from a higher base going forward.

Implications for Advisor Portfolios

The historical evidence from 2008, 2020, and 2022 points to several conclusions:

1. Low-volatility stocks reduce but do not eliminate crash losses. They are a better version of equity exposure, not a substitute for risk management.
2. Bonds are not a guaranteed hedge. In rate-driven downturns, bonds can fall alongside equities. The 60/40 portfolio is a long-term framework, not a crash protection mechanism.
3. Cash is the only true safe haven, and the ability to systematically rotate to cash is the most direct form of downside mitigation available in an ETF format.
4. Speed of response matters. Strategies that adjust based on signals rather than calendar schedules can respond to rapidly changing conditions. Fixed rebalance dates are a structural disadvantage during fast-moving markets.
5. Systematic beats discretionary during stress. The worst time to make portfolio decisions is during a crisis. The best strategies are those that make the decision in advance through predefined rules.

For advisors building portfolios designed to survive the next crash, the question is not if it will happen, but when. The tools available today, including ETFs that can systematically rotate to cash, provide capabilities that simply did not exist in ETF form during prior crises. Using them is not about predicting the future. It is about being prepared for the range of outcomes that history has already shown us are possible.