The world's population of ultra-rich people is growing, but at an almost startling level in Asia, according to a new study.

This year's World Ultra Wealth Report by research organization Wealth-X included a ranking of cities that have the highest population of ultra-wealthy residents, with the study defining ultra-wealthy as a net worth of $30 million or more.

The ranking illustrated some of the gains that residents in Asia have made in terms of wealth. For example, that of the cities with the fastest-growing UHNW populations in the world between 2012 and 2017, 26 are in China, three are in the U.S. and only one, Dublin, lies outside those nations.

The world's UHNW population grew to 255,810 people in 2017. Women comprised almost 35,000, or 13.7 percent, of the UHNW population.

Over 60 percent of UHNW individuals stated that their wealth accumulation was self-made, with the financial industry, manufacturing and technology representing the primary industries for wealth creation.

Compared with 2017, the ultra-high-net population is expected to rise to 360,390 people by 2022, which is an increase of almost 105,000 people. UHNW wealth is estimated to increase by $12.8 trillion to $44.3 trillion, in the next five years, according to the report.

These, according to the Wealth-X report, are the cities with the highest UHNW populations, in ascending order:

10. Osaka, Japan

Osaka grew its UHNW population by 11.7 percent in one year to 2,730.

9. Washington D.C.

The U.S. capital has 2,735 ultra wealthy individuals, which is 7.7 percent growth in 2017.

8. San Francisco

San Francisco increased its high-net-worth population by 10.6 percent to 2,820 in one year.

7. Chicago

The Windy City reported 3,255 ultra-wealthy individuals in 2017 for an increase of 7.1 percent.

6. London

With an increase of 10.1 percent, London had a population of 3,830 UHNW residents in 2017.

5. Paris

There were 3,950 high-net-worth individuals living in Paris in 2017, for a 17.3 percent change in just one year.

4. Los Angeles,

California’s Tinsel Town saw an increase of 8.6 percent in its ultra-wealthy population for a total of 5,250.

3. Tokyo

Japan’s capital city increased its wealthiest population by 11.9 percent to 6,785 in one year.

2. New York City

Knocked off the top city for the UHNW, the Big Apple still grew by 7 percent with 8,865 individuals in 2017.

1. Hong Kong

The city is seeing a booming growth in wealth. Its wealthy population grew by 31 percent to 10,010 last year.