Volatility Targeting: How the Strategy Works and When It Fails

Volatility targeting is a rule that scales a portfolio's exposure to hold its risk near a fixed level. When markets get jumpy, it owns less. When they calm down, it owns more.

The target is a number, usually an annualized volatility such as 10 percent. The rule divides that target by the volatility it's measuring today. The answer is how much of the portfolio stays invested.

What is volatility targeting?

Most portfolios hold a fixed mix and let the risk float. A 60/40 portfolio is always 60/40. Its volatility might be 6 percent one year and 20 percent the next.

Volatility targeting flips that. It fixes the risk and lets the mix float. The equity weight becomes an output, not an input.

The idea rests on one observation. Volatility clusters. A calm week tends to follow a calm week, and a wild week tends to follow a wild one. Returns are hard to forecast. Next month's volatility is much easier.

How does a volatility targeting strategy work?

1. Set the target. Pick an annualized volatility level. Equity strategies often use 10 to 15 percent. Conservative ones go lower.
2. Measure current volatility. The simplest version uses the standard deviation of daily returns over the last 21 trading days, annualized.
3. Divide. Exposure equals the target divided by measured volatility. A 10 percent target with 20 percent measured volatility gives 50 percent exposure.
4. Cap it. Set a maximum. Unlevered strategies cap at 100 percent. Levered ones might allow 150 or 200.
5. Park the rest. The uninvested share sits in cash or short-term Treasuries.
6. Rebalance. Daily, weekly or monthly. Faster rebalancing tracks the target more closely and trades more.

That's the whole engine. Everything else is a choice about the lookback window, the cap and how often to trade.

What does volatility targeting look like in a real crash?

Take a 10 percent target on the S&P 500, with 21-day realized volatility and a 100 percent cap. Here's what the rule would have said on dated closes in 2020.

• 19 February 2020. The index closed at a record 3,386. Realized volatility was 13.0 percent. Exposure: 77 percent.
• 28 February. The index was down 12.8 percent from the peak. Realized volatility had jumped to 24.5 percent. Exposure: 41 percent.
• 23 March. The index bottomed at 2,237, down 33.9 percent. Realized volatility was 84.7 percent. Exposure: 12 percent.
• 6 April. Realized volatility peaked at 97.6 percent. The rule held about a tenth of the portfolio in stocks.
• 30 June. The index was up 38.6 percent from the low. Realized volatility was still 30.5 percent. Exposure: 33 percent.
• 31 August. The index closed at 3,500, above the February record. Realized volatility fell to 8.1 percent. Exposure: back to 100 percent.

Read that list twice. It tells both halves of the story.

The rule cut risk fast. By the bottom it held about an eighth of what it held at the top. But the first 13 percent of the fall hit a portfolio still one-half to three-quarters invested. A 21-day window needs a few bad days before it notices.

Then the rebound. From 23 March to 31 August the index gained 56.4 percent. The rule spent most of that stretch between 12 and 33 percent invested. It rebuilt exposure only once the market was calm again, which was after the recovery.

2022 looked different. The S&P 500 fell 25.4 percent from 3 January to 12 October. Realized volatility ran between about 13 and 34 percent. The same rule sat between roughly 30 and 75 percent invested on the way down. A slow, grinding bear market is where volatility targeting tends to look its best.

Volatility targeting vs risk parity: what's the difference?

They're related, and people mix them up.

Risk parity is about the split between assets. It sizes each holding so every one contributes the same risk. Volatility targeting is about the size of the whole book. It scales total exposure to hit one risk number.

Many risk parity funds use both. They balance risk across stocks, bonds and commodities, then lever the whole portfolio up to a volatility target. You can also run volatility targeting on a single asset, as in the example above.

Which volatility measure should a volatility targeting fund use?

There are three common choices.

• Short realized volatility. Twenty to sixty trading days. Reacts fast and whipsaws more.
• Long realized volatility. Six months to a year. Smoother, and slow to react to a sudden shock.
• Implied volatility. The VIX or option prices. Forward-looking, but it spikes on fear that doesn't always turn into losses.

Plenty of volatility targeting funds blend a short and a long window. The blend trades some speed for fewer false alarms. No setting is right in every market. That's the point of knowing which one a fund uses.

How do volatility targeting funds use leverage?

In calm markets the math asks for more than 100 percent. With 8 percent realized volatility and a 10 percent target, the rule wants 125 percent exposure.

An unlevered strategy just stops at 100. A levered one borrows or uses futures to reach the number. That's why two funds with the same target can behave very differently. Always check the cap in the prospectus. It matters as much as the target.

When does volatility targeting fail?

This is the part to read before you allocate.

• Sudden gaps. The rule reacts to volatility that has already happened. A one-day crash from a calm starting point hits at full exposure. On 16 March 2020 the S&P 500 fell 12 percent in a single session.
• V-shaped recoveries. Volatility stays high after the low. The rule stays small while prices snap back, as it did from March to August 2020.
• Crowded selling. Many funds run similar rules. When volatility jumps, they all cut at once. That selling can add to the move it's reacting to.
• Calm markets that turn. Low volatility pushes exposure to the cap. A levered fund is at its largest just before a shock.
• Trading costs. Daily rebalancing on a short window can turn over the portfolio many times a year. Costs and taxes add up.

Volatility targeting seeks to keep risk steady. It doesn't promise a smaller loss. It changes when you take losses, and it changes when you miss gains.

Is volatility targeting the same as market timing?

Not quite. Market timing tries to forecast direction. Volatility targeting doesn't care about direction at all. It reacts only to how much prices are moving.

In practice the two overlap, because volatility tends to rise when markets fall. That's why the rule often cuts exposure in a decline. It's a side effect of the risk math, not a forecast. Rules that do use direction sit on the other side of that line. Trend following is one. A cash signal is another. THOR's indexes use a signal-driven cash step, not a volatility scale. Different answer, same problem.

For advisors managing clients who draw income, the timing of losses matters more than their size. The sequence of returns risk guide shows why. A low volatility ETF is another route to less risk, by stock selection instead of exposure.

Volatility targeting: definitions

• Volatility targeting. Scaling total exposure up or down to hold portfolio volatility near a fixed number.
• Target volatility. The annualized standard deviation the strategy aims to hold, such as 10 percent.
• Realized volatility. The annualized standard deviation of past returns over a set window.
• Implied volatility. The volatility priced into options, such as the VIX for the S&P 500.
• Exposure cap. The maximum share of capital, or leverage, the rule may hold.
• Volatility clustering. The tendency of high-volatility days to follow high-volatility days.

Past performance is not indicative of future results. Index figures cited above are public market data for illustration only. The exposure levels come from a simple rule applied to public index data. They are not the holdings or performance of any THOR fund or strategy. This material is not investment advice.