It isn't easy staying a billionaire. Here's why

'Making a billion dollars is easy, keeping it is hard'
'Making a billion dollars is easy, keeping it is hard'

In the HBO show "Silicon Valley," billionaire tech investor Russ Hanneman breaks down after learning that his 10-figure fortune shrunk to a mere $986 million, ousting him from the "three comma club."

"I'm financially ruined," he sobs. "I'm not a billionaire anymore. ... I'm a 986-ionaire, which isn't even a f------ thing."

Hanneman's comma trauma makes for great comedy. But it turns out, falling out of the billionaire club is surprisingly common.

According to a new study from UBS and PwC, only 44 percent of global billionaires in 1995 maintained that status through 2014. That means 56 percent of the billionaires in 1995 lost a comma — and sometimes more — in roughly 20 years.

Russ Hanneman, played by Chris Diamantopoulos, on HBO's "Silicon Valley."
Source: HBO

Granted, many of these former billionaires are still wealthy by almost any measure. But the finding shows just how volatile and fleeting today's wealth has become, as big fortunes are more closely tied to stock markets, changing technologies and the vagaries of the global economy.

"The billionaire population has changed beyond recognition over the past 20 years," according to the UBS/PwC Billionaire report. "This partly reflects the extraordinary number of newly-minted billionaires ... yet what's easily overlooked is the volatility of great wealth."

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Indeed, most of 2014's billionaires were newly minted, or at least new since 1995. There were 289 billionaires in the world in 1995, but 1,347 in 2014 — proving that most of today's billionaires have made their fortunes fairly recently.

The billionaires who kept their fortunes over the 19-year stretch into 2014 have seen their combined wealth grow by more than $1 trillion, from $365 billion to $1.38 trillion.

Yet among the 289 billionaires in 1995, only 126 made it to 2015. Seventy-three lost their billionaire status due to business problems or failures, and 24 lost their status through family dilution. And, of course, death took its inevitable toll: 66 of the 1995 billionaires died.

So, other than staying alive, what's the secret to maintaining billionaire status?

It helps to be a tech founder. According to the study, technology has doubled its share of billionaire wealth, from 10 percent in 1995 to 20 percent in 2014. Consumer and retail founders and executives have also done well, accounting for 32 percent of 2014 billionaire wealth. It also helped to be a billionaire in the U.S., since they saw the biggest wealth gains globally.

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The report also pointed to three personality traits common to self-made billionaire entrepreneurs: Smart risk taking, "obsessive" business focus and dogged determination. Among the inherited wealthy who seek to preserve their wealth and family business, the report said that "managerial competence must override family ties."

It also said that "maintaining a strong identity has proven material to long-lasting billionaire family dynasties," and that "strong governance and a well-resourced family office is a key factor in building lasting legacies."

Still, the report said that maintaining billionaire wealth may become even harder in the years to come, given the political backlash worldwide against the rich.

"Anti-wealth sentiment in politics, growing taxes and increasingly stringent global regulations pose the biggest threats to billionaires' wealth," the report said.