Billionaire investor Warren Buffett says he worries about a few things. The success of his company isn’t one of them.

Asked if he was worried about Berkshire Hathaway’s trajectory amid current economic headwinds, from banking failures to rising interest rates, the 92-year-old recently made his feelings clear on CNBC’s “Squawk Box.”

“At 92, I’ve got other things to worry about … I worry about the nuclear threat. I worry about a pandemic in the future, all kinds of [things],” Buffett said. “I never go to bed worried about Berkshire and how we’ll handle a thing.”

Since Buffett took over Berkshire Hathaway in 1965, the company has grown to become one of the world’s largest, with a market capitalization above $707 billion and a portfolio of investments including Geico, Dairy Queen, Duracell and Fruit of the Loom.

Buffett also has a well-documented history of optimism — one that close friends like Melinda French Gates credit for his success. In 2017, a data scientist performed a sentiment analysis on decades of Buffett’s annual letters to Berkshire’s shareholders, and identified a surplus of positivity in Buffett’s updates.

It shows in his investment strategies: Buffett is a known proponent of choosing investments you believe in, regardless of their current price, and taking advantage of stock drops to buy more of companies you trust.

When stocks are down, “I would tell [investors], don’t watch the market closely,” Buffett told CNBC in 2016 during a volatile market period.

His optimism is rooted in a supreme sense of self-confidence. “99 and a fraction percent of my net worth in Berkshire,” Buffett told “Squawk Box,” adding that multiple of his family members also heavily invest in the company.

“If I thought that I wasn’t going to be able to do a decent job of managing the risk, a better than decent job, I’d be crazy to take on that responsibility,” Buffett said.

When Buffett encounters a scary issue that’s outside of his control — like a nuclear war or future pandemics — he tries to mitigate his stress by focusing on situations and tasks that he can actually remedy himself, he said.

“I worry about things nobody else worries about, but I can’t solve them all,” Buffett said. “I can’t solve if the pandemic starts. But anything that can be solved, I should be thinking about that.”

As for feeling secure about Berkshire’s future, Buffett has already handpicked his company’s next CEO — and his successor, Greg Abel, has said he doesn’t plan to diverge from Buffett’s winning formula. Buffett is known to trust the leaders at Berkshire’s portfolio companies to make the right business decisions, and he expects Abel to follow suit.

“I am not giving [Abel] some envelope that tells him what to do next,” but Berkshire Hathaway is “so damn lucky” to have Abel taking the reins, Buffett said.

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