The Yellowstone Factor: Minimizing Downside Risk

Written by

Jae Jun

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What You’ll Learn

  • What is the Yellowstone factor and what’s it got to do with investing?
  • How do you minimize downside risk

With the weather warming up, kayaks on the water and RV’s heading towards Yellowstone, Mohnish Pabrai wrote about the Yellowstone factor that is short and sweet.

Mohnish Pabrai knows his geography.

“Yellowstone National Park is volcanic in nature, yet not one cone or caldera is visible. In the 1960s, this mystery was finally solved: The entire park — 2.2 million acres — is the caldera. It is the largest active supervolcano on Earth. Yellowstone started erupting about 17 million years ago, and it has a cycle of erupting roughly every 600,000 years. The last eruption was 630,000 years ago, so it’s about 30,000 years past due on the next big one.”

Although Yellowstone is closer to the west coast, if it explodes, the entire country will be devastated. There’s always talks about volcanoes being overdue, to the point where it’s like crying wolf.

But that is the reality of the Yellowstone Factor in life and in the markets.

  • It’s a catastrophic event that is highly unlikely to happen. But it also means that the probability of it happening is not 0%.
  • The Yellowstone Factor alone implies that not a single business has a safe future.

“Minimizing risk is the first step toward being a successful investor.”

Other categories that fall into the “Yellowstone” category include:

  • war
  • terrorism
  • fraudulent financial statements
  • dishonest management
  • disruptive innovation

The goal isn’t to have an accurate probability of each happening. It also does not revolve around precise math.

Pabrai also mentions that he doesn’t need to use spreadsheets to know a good investment. 

Seeing as how Old School Value sells spreadsheets, my counter is that we provide a framework, a manageable field of investment ideas and helping you find the true value range.

Much like when you go car shopping. There’s a sticker price (the stock market price) but the true price you pay is within a certain range. And unless you look at cars all day, every day, you won’t know what that good range is. And that’s where you should use tools to quickly get through this step instead of getting paralyzed.

With investing, back of envelope calculations and internal rules of thumbs are very important. There simply aren’t enough data points available to work out the exact odds.

So what’s the way to quickly minimize risk?

  1. invest in what you know or comfortable with. This will help you stay in control.
  2. buy well-run and good businesses to put the odds in your favor.
  3. buy with a margin of safety so that even if you lose, you don’t lose much.

With 3 simple (but tough) rules to follow, your portfolio will be balanced to withstand the Yellowstone factor if it does come occur.

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