It took Warren Buffett 26 years. Bill Gates? Only five.

But the record for fastest route from millionaire to billionaire currently goes to Facebook FB, +2.66% CEO Mark Zuckerberg, who took just one year to make the leap, according to a study by Betway based on Forbes’ annual “World’s Billionaires” ranking.

Zuckerberg’s path was lighting fast compared to the Berkshire Hathaway BRK.A, +0.33% CEO and investing guru, or to Koch Industries owner Charles Koch, who took 22 years to get there.

Here’s a list of the 25 richest people in the world in 2018, according to Forbes, followed by the number of years it took them to go from millionaire to billionaire, as compiled by Betway:

Zuckerberg was the youngest self-made billionaire to ever appear on the Forbes Billionaires list when he debuted in 2008 at the age of 23. He didn’t make the 2009 list, with his estimated net worth dropping below $1 billion, but it didn’t take long before Facebook’s valuation started to go way up, and Zuckerberg’s net worth along with it.

The analysis shows that founding a major tech company has been one of the fastest routes to billionaire-dom. Amazon AMZN, +5.69% founder Jeff Bezos took two years to leap from millionaire to billionaire, while both Microsoft MSFT, +2.40% founder Bill Gates and Google GOOG, +2.39% GOOGL, +2.07% co-founders Larry Page and Sergey Brin took five years to get there.

Related read:Warren Buffett explains what’s wrong with the economic system that made him billions

Related read: The No. 1 financial fear among rich people should have you seriously concerned

Almost a quarter of the billionaires analyzed by Betway had a degree in engineering, and about 20% had a degree in economics or business. About a third didn’t have a college degree at all.

There are now more than 2,000 people in the world who are worth at least $1 billion, a figure that has doubled in the past decade. Among those 2,000 people, the average age they joined the billionaire’s club was 51. Jeff Bezos was 35 when he became a billionaire, while Bill Gates was 31.

Of course, being a billionaire isn’t always what it’s cracked up to be. People aren’t exactly thrilled with Zuckerberg right now in light of the news surrounding Facebook’s data scandal. He publicly apologized on CNN last month, and will testify before lawmakers next week.

“This was a major breach of trust and I’m really sorry this happened.” he said to CNN’s Laurie Segall. “Our responsibility now is to make sure this doesn’t happen again.”