So, is that number reason to celebrate? On one hand, 145 is a huge increase—almost sevenfold—from twenty years ago, when only 22 women hit the billion dollar threshold. However, world’s 1,202 male billionaires still outnumber their female counterparts by more than 8-to-1, according to a report by UBS and PwC.

The vast majority (80%) of ultra-wealthy women are based in Europe and the U.S. But while most of these billionaires inherited their wealth (81% in the U.S. and 93% in Europe), more than half of the 25 Asian female billionaires are self-made, according to the report.

Though 25 may seem like a relatively small number, it’s a huge jump from a decade ago, when there were just three female billionaires in Asia. These women also tend to be younger than their Western counterparts, with an average age of 53, compared to 59 in the U.S. and 63 in Europe.

Many of the Asian women on the list who built their wealth themselves worked hard to pay for Western education, then returned to Asia to make their fortunes. “After working in a factory for some years, I saved sufficient to study abroad and get a degree,” said one billionaire in the study.

This story sounds a lot like that of the wealthiest self-made woman in the world, Zhou Qunfei, a Chinese factory worker-turned-founder of touch screen manufacturing company Lens Technology. She is one of eight Chinese women on a list of the world’s ten wealthiest self-made women, which was published earlier this fall.

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