In the week following President Donald Trump’s announcement of sweeping tariffs, the S&P 500 briefly flirted with bear territory — defined as a 20% decline from recent highs — as worries swirled that the levies would reignite inflation and set off a trade war that could slow the global economy.

But on Wednesday, the President announced a 90-day pause on tariffs exceeding 10% for some countries, while raising duties on Chinese products to 125%. The S&P 500 climbed more than 9% on the day.

Even if they don’t typically come this rapidly, large swings in stock prices are part and parcel of being an investor. Take it from the late Charlie Munger, the longtime vice-chairman of Berkshire Hathaway and right-hand man to Warren Buffett.

“I think it’s in the nature of long-term shareholding that the normal vicissitudes in markets means that the long-term holder has the quoted value of his stocks go down by, say, 50%,” Munger told a BBC interviewer in 2009.

If you’re not willing to keep your chin up during the occasional rout, he continued, “you’re not fit to be a common shareholder, and you deserve the mediocre result you’re going to get compared to the people who can be more philosophical about these market fluctuations.”

Munger was speaking from experience. In 2009, shares in Berkshire Hathaway, which made up a sizeable portion of his portfolio, had declined by more than 50%. When asked if he had any worries about the state of the company and its stock, Munger cut off the interviewer.

“Zero,” he said. “This is the third time that Warren and I have seen our holdings in Berkshire Hathaway go down, top tick to bottom tick, by 50%.”

Each time, Berkshire Hathaway continued to invest in the stock market, with Munger and Buffett following the latter’s famous maxim: “Be fearful when others are greedy, and be greedy when others are fearful.”

That meant consistently buying stocks the pair saw as undervalued and having faith that U.S. businesses would return to boosting profits. Berkshire’s portfolio, just like the broad U.S. stock market, found new highs after each major drawdown.

Times of uncertainty and volatility in the stock market can be scary. But if you’re around for long enough, you’ll likely live through a few of them, Munger said.

“I think you can count on more booms and busts over your remaining lifetime. How big and with what cyclicality, I can’t tell you,” Munger told students at the University of Michigan in 2011 — another tumultuous year for stocks. “I can tell you the best way of coping, which is to just put your head down and behave creditably every day.”

In general, financial experts advise long-term investors to continue buying stocks through downturns. Historically, the long-term upward trajectory of the stock market has made such periods look like times to buy stocks on sale. In essence, if you already invest regularly, say, through a 401(k), you can leave things on autopilot.

Munger advised the crowd in Michigan that major drawdowns were rare opportunities to build wealth, recalling the advice of his great grandfather.

“Real opportunities that come to you are few,” he said, adding that almost no one is “bathed” in good fortune. “Most people just get a few times when they can make a huge difference by seizing a huge activity.”

For investors, when you have the opportunity to buy assets at a huge discount, it’s important to seize the moment to the best of your ability, and not leave your money sitting on the sidelines while you wait for things to get better, Munger said.

“When you get a lollapalooza, for God’s sakes, don’t hang by like a timid little rabbit,” Munger said. “Don’t hang back.”

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