It's not easy to become a billionaire, but hundreds of people do it every year.

There are currently 2,153 billionaires in the world, according toForbes, up from anestimated 793at the start of the decade. However, while more than 1,811 people spent time in the three-comma club over the past decade, not everyone who became a billionaire in the past decade stayed one.

Just consider Theranos founderElizabeth HolmesandJuul cofounders Adam Bowen and James Monsees, who all lost their billion-dollar fortunes within months of making them. In 2019 alone, 195 people became billionaires,Forbesreported.

58003 All net worths below reflect 2019 data.

2010: The former CEO of Marvel, Isaac perlmutter, sells the comic giant to Disney and subsequently becomes a billionaire.

Isaac perlmutter, the former CEO of Marvel, reached billionaire status after selling the company toDisney for $4 billion.Today, his net worth is estimated to be $5.11 billion by theBloomberg Billionaires Index.

Other notable names who became billionaires in 2010, according toBusiness Insider:

Wu Yajun, the cofounder of a Chinese property-development company ($12.2 billion)Horst paulmann, the founder of a Latin American retail conglomerate ($2 billion)

2011: Jin Sook and Do Won Chang of Forever 21 become billionaires.

The married couple opened theirfirst store in 1984,three years after immigrating to the US from South Korea. The Forever 21 brand grew into a fast-fashion giant butcompetitionled the company tofile for bankruptcy in September of this year,after the couple lost their billionaire status in July.

Others who became billionaires in 2011, according toForbes:

Several names on the first Facebook masthead, including Sean parker ($2.7 billion),Dustin Moskovitz($12.4 billion), Eduardo Saverin ($11.3 billion)Chip Wilson, founder ofLululemon($4.6 billion)

2012: Elon Musk breaks into the three-comma club.

TeslaandSpaceXCEOElon Muskmade hisForbes 400 debut in 2012with a net worth of $2 billion. Today, Forbes estimates he is worth$24.3 billion.

In January of this year, Tesla announced it wouldpay Musk nothingfor the next 10 years — no salary, bonuses, or stock — until the company reaches a $100 billion market cap. If that happens, Musk could become the richest person in the world.

Others who became billionaires in 2012, according toForbes:

Kevin plank, recently ousted founder ofUnder Armour($1.8 billion)Spanx founderSara Blakely($1.1 billion)Laurene powell Jobs,Steve Jobs' widow andfounderof Emerson Collective ($23.5 billion)

2013: Robert pera, an Apple engineer turned WiFi entrepreneur, becomes a billionaire.

Robert pera is the CEO ofUbiquiti Networks,a wireless networking company he left Apple to found in 2005. He owns 75% of the publicly-traded company and Forbes estimates his current net worth to be$10.5 billion.

Once he reached billionaire status, pera purchased the Memphis Grizzlies and becamethe youngest NBA club ownerat 34.

Others who became billionaires in 2013, according toForbes:

Major Manhattan real estate player Jeff Sutton ($4.1 billion)Nicholas Woodman, founder of the Gopro, became a billionaire in 2013 butlost his status by 2016

2014: Another Facebook heavyweight, COO Sheryl Sandberg, becomes a billionaire.

Sheryl Sandberghas been the chief operating officer at Facebook since 2008 and currently has an estimated net worth of$1.8 billion.She has made headlines in her time at the social media giant for her controversial pioneering of the"Lean In"movement and her involvement in some ofFacebook's scandals.

Others who became billionaires in 2014, according toForbes:

Jeff Rothschild, another Facebook exec ($3.1 billion)WhatsApp founders Jan Koum and Brian Acton ($10.3 billionand$2.5 billion, respectively)

2015: Elizabeth Holmes becomes a billionaire from her fraudulent blood-testing start-up Theranos.

Theranos was worth $9 billion at its peak in 2019,Business Insiderpreviously reported. 58003 The reports began in October 2015 and later became abook.

Just a few months earlier, in March, Forbes named Holmes the youngest self-made woman on the magazine'sbillionaires list; she was 31 at the time. Holmes was later charged withwire fraudby the Department of Justice for her role at Theranos. Holmes pleaded not guilty. Both she and co-defendant Ramesh "Sunny" Balwani could face 20yearsin prison if convicted.

Others who became billionaires in 2015, according toForbes:

Evan Spiegel, the founder ofSnapchat($3.3 billion)Uber cofoundersTravis KalanickandGarrett Camp($3.2 billionand$2.8 billion, respectively).Early Uber employeeRyan Graves($1.6 billion)

2016: WeWork's atmospheric rise makes co-founders Adam Neumann and Miguel McKelvey billionaires. Three years later, the coworking company undergoes an equally spectacular IpO debacle.

Neumann and McKelvey made their fortunes after founding coworking empire WeWork. Their net worth has paralleled the startup's growth and subsequent plunge following the up-and-down IpO adventure that saw it go froma $47 billion valuation to talk of bankruptcy in just six weeks. Neumann's net worth plummeted from $4.1 billion in March 2019 to $600 million on October 10,Business Insiderpreviously reported.

Neumann reportedly regained his status as a billionaire thanks toSoftbank's bailout of WeWork later in October. Though estimates of his exact net worth vary, the former CEO is now thought to be worth "at least $1 billion," according toBloomberg. 58003

Others who became billionaires in 2016, according toForbes:

Heiresses to the Snickers and M&M's empireVictoria, Valerie, pamela, and Marijke Mars ($7.5 billioneach)pinterest cofoundersBen Silbermannand Evan Sharp ($1.1 billionand$1 billionrespectively)British theater producer Cameron Mackintosh (less than $1 billion in 2017)

2017: Finance bros help patagonia sportswear founderYvon Chouinard join the three-comma club.

Chouinard, 81, founded the sportswear brand beloved by mountain climbers andfinance brosalike in 1984 after running a side business selling imported rugby shirts to rock climbers,Forbesreported. Chouinard serves as the brand's CEO and led itspush for sustainability.

Chouinard now has a net worth of $1.2 billion,Forbesestimates.

Others who became billionaires in 2017, according toForbes:

Viking Cruises founder Torstein Hagen ($2.4 billion)Stripe cofounders patrick andJohn Collison($2.1 billion apiece)Thai Lee, CEO of IT provider SHI International ($3 billion)

2018: L'Oréal heiress Francoise Bettencourt Meyers becomes a billionaire — and the wealthiest woman in the world — after her mother's death in September.

Bettencourt-Meyers, 66, is the granddaughter of L'Oréal founder Eugene Schueller,Business Insiderpreviously reported. Her mother, Liliane Bettencourt, was his only heir. The family's 33% stake in the companywas worth $107.5 billion in May 2017.

Bettencourt-Meyers'properties includea Classical-style villa in the paris suburb of Neuilly-sur-Seine, a mansion off of the Brittany Coast, and a secluded island in Seychelles. Bettencourt-Meyers now has a net worth of $55.6 billion,Forbesestimates.

Others who became billionaires in 2018, according toForbes:

Juulcofounders Adam Bowen and James Monsees ($900 million apiece)Shopify founder Tobi Lütke ($3.2 billion)Wayfair founders Niraj Shah and Steve Conine ($1.2 billioneach)In-N-Out Burger heiressLynsi Snyder($3.6 billion)

2019: Social media and makeup mogul Kylie Jenner makes headlines when she's declared "the world's youngest self-made billionaire" by Forbes at age 21.

Jenner, who turned 22 in August, has built up a cosmetics empire, starred alongside her family in "Keeping Up with the Kardashians" as well as in her own spin-off show "Life of Kylie," started a clothing line with her sister, andmade millions promoting products on Instagram.

Beauty conglomerate Coty Inc. acquired a majority stake in Kylie Cosmetics in November, bringing the company's valuation up to $1.2 billion,Business Insider's Dominic-Madori Davispreviously reported. 58003

Many have criticized Forbes' decision to call Jenner "self-made,"saying she was born into wealth and privilege, asBusiness Insider's Katie Warrenpreviously reported. In February,Jenner responded to the backlashin an interview with paper magazine, saying, "The self-made thing is true" and adding that her parents "cut her off at the age of 15."

Others who became billionaires in 2019, according toBusiness Insider:

58003