UBS, the world's largest private bank, keeps getting bigger and increasingly more of that growth is coming from Asia and, in particular, its women.

So what else is new? After all, as the rich get richer, and with a turbo-charged China, the fact that more of them are women is to be expected.

UBS Wealth Management Asia-Pacific's invested assets grew a record US$95 billion (S$125 billion) to US$382.8 billion last year, and made a strong profit contribution of 21 per cent to the Swiss bank's global wealth management division.

But while making it into the big time, either as salaried workers or entrepreneurs, women remain a minority in the overall scheme of things - though as Mao Zedong famously once said, "they hold up half the sky". Whatever male comrades can accomplish, female comrades can too, he added.

Ms Tracey Woon, UBS vice-chairman, Asia-Pacific, wealth management, is certainly very accomplished. An investment banker for 35 years, Ms Woon is at the top of her game, and she surprised some when she joined UBS in July 2016, leaving her position as vice-chairman of Citibank Asean corporate and investment banking.

"When I made my move, a lot thought I was going to retire - not have another career," she said. "Going from a US bank to a European wealth manager really excited me."

She likes the new challenge, that UBS is big on philanthropy and that she will be talking to some of the richest people in the world. To be clear, she "covers all clients, though the bulk of them are billionaires". She said: "My remit is providing strategic advice and dialogue to some of the wealthiest people in the world."

According to the 2017 UBS/PwC billionaire study, the number of Asian billionaires stood at 637, of which 6 per cent, or 39 of them, are women. For the first time, Asian billionaires outnumbered their 563 counterparts in the US, but the US still retains the greatest concentration of wealth, the study said. If the current trend continues, the total wealth of Asian billionaires will overtake that of US ones in four years.

Asia's 637 billionaires were boosted by 162 newbies. China led the pack with 101 new billionaires. Billionaire wealth in other key Asian markets (Hong Kong, Singapore and Japan) grew by almost 30 per cent.

The rising number of female billionaires in Asia is impressive. Asia's female billionaires increased by almost 13 times from 2005 to 2016 to make up 6 per cent of the total Asian billionaire population.

In contrast, it was flat in the US, while Europe saw a small decrease over the last two years.

The study showed that around 70 per cent of Asia's female billionaires are self-made, compared with a global average of 26 per cent. It was 17 per cent in the US, and 7 per cent in Europe.

Some of Asia's wealthiest females are business owners who might be interested in corporate activities for their businesses - such as large asset sales, mergers and acquisitions, initial public offerings, and other large capital-raising activities - and are looking for banks with the capabilities to execute.

Helping business owners with their corporate activities would be a cinch for Ms Woon, who during her time at Merrill Lynch was involved in Singapore's largest takeover: the $10 billion acquisition of Overseas Union Bank by United Overseas Bank in 2001.

All investors generally look for the best investment returns, but research has shown that in stark contrast to men, women are more focused on investing to achieve positive social change, said Ms Woon.

A study by the US-based Centre for Talent Innovation found 88 per cent of women want to invest in organisations that promote social well-being. Female investors could be set to invest US$2.3 trillion in improving social good by 2021, according to a UBS calculation based on a Capgemini World Wealth Report.

The bank last year made it a priority with a five-year plan to significantly scale up its expertise to better serve female clients. "Women do invest very differently from men - they think not just about generating a financial return," said Ms Woon.

They do not think only about US Treasuries; they are also interested in World Bank bonds and green bonds, she said.

When asked about her own career, in which she has not only thrived but also risen to the top in the very tough investment banking world, she said women have differences they can capitalise on. "Men find it harder to fight with women."

On getting things done, "when it comes to the actual financial outcome, the givens are how smart you are, how you run the numbers".

"The difference is how you deal with the situation, how you put things across... Women have more options than men."

There are also no shortcuts to being disciplined and focused on the endgame, she said.

"I've always thought it's possible to have a work-life balance," said Ms Woon, whose spouse is a house husband. Even so, she has had to make sacrifices when her three children were young. She gave up golf, which is well known to be a time-consuming pastime. Her competitive nature also made her give up another sport. A five-time national squash champion, she stopped playing the sport because she "hates losing".

She did not have much of a social life either, she said.

Has she faced sexual harassment at work or hurdles which a male colleague might not encounter?

Women are "intuitive" and "anticipatory", and "you can see it coming and don't let yourself get into that situation", said Ms Woon. You have to figure out the situation before it blows up, she said.

Describing herself as tough, she said her reputation meant she was the perfect candidate for sexual harassment officer at Merrill Lynch. She was with the US firm from 1989 to 2004. "They decided that if I was the sexual harassment officer... I'd harass everyone else." She might have been seen as a tough cookie, but that was just a perception, she mused. "People always say you're the fiercest, the nastiest person, and I'd say when did I ever scold you?"