For those keeping score, 2014 was very good year for ultra high-net-worth individuals in the U.S with their total assets rising 9%, to $15.2 trillion. In the top dozen cities alone, wealth rose by more than a trillion dollars.

According to Capgemini’s 2015 U.S. Wealth Report, the areas of the country that saw the biggest rise in HNWI residents were in Texas and the West Coast, mainly because of growth in real estate prices. Capgemini defined HNWI as those with at least $1 million of investable assets excluding primary residence, collectibles, consumables and other consumer durables.

North America is second in the world to Asia-Pacific in sheer numbers of HNWI. North America is close with 4.68 million individuals compared to 4.69 million in Asia-Pacific.

With the U.S. economy getting back on it feet, it would seem the rise in the ultra-wealthy is likely to continue, although the mysteries of the stock and real estate markets may cause things to change.

Check out the Top 12 Fastest Growing U.S. Cities for Millionaires:

(Related on ThinkAdvisor: Top 10 States With the Most Millionaires: 2015 and Top 10 Big Trends Among the Ultra-HNW)

Millennium Monument at Chicago's Millennium Park. (Photo: AP)

12. Chicago

% Rise in HNWI: 6.7%

No. of HNWI : 282,000

Total Wealth (% change): $1.163 trillion (7.8%)

Washington, D.C. Skyline.

11. Washington, D.C.

% Rise in HNWI: 7%

No. of HNWI : 236,000

Total Wealth (% change): $957 billion (8.1%)

Brooklyn Bridge with Manhattan in background.

10. New York

% Rise in HNWI: 7.7%

No. of HNWI : 963,000

Total Wealth (% change): $3.528 billion (8.8%)

Philadelphia's Liberty Bell. (Photo: AP)

9. Philadelphia

% Rise in HNWI: 7.9%

No. of HNWI : 146,000

Total Wealth (% change): $600 billion (9%)

Hart Plaza in Detroit. (Photo: AP)

8. Detroit

% Rise in HNWI: 7.4%

No. of HNWI : 116,000

Total Wealth (% change): $468 billion (8.5%)

Beacon Hill in Boston.

7. Boston

% Rise in HNWI: 9.7%

No. of HNWI : 162,000

Total Wealth (% change): $618 billion (10.8%)

Hollywood Sign.

6. Los Angeles

% Rise in HNWI: 10.4%

No. of HNWI : 364,000

Total Wealth (% change): $1.335 billion (11.5%)

Lombard Street in San Francisco.

5. San Francisco

% Rise in HNWI: 11.2%

No. of HNWI : 364,000

Total Wealth (% change): $794 billion (12.3%)

Dallas skyline. (Photo: AP)

5. Dallas

% Rise in HNWI: 11.2%

No. of HNWI : 126,000

Total Wealth (% change): $513 billion (12.4%)

San Jose City Hall

3. San Jose, Calif.

% Rise in HNWI: 11.4%

No. of HNWI : 136,000

Total Wealth (% change): $505 billion (12.5%)

A view of Seattle's Space Needle and skyline. (Photo: AP)

2. Seattle

% Rise in HNWI: 12.1%

No. of HNWI : 98,000

Total Wealth (% change): $348 billion (13.3%)

Lyndon B. Johnson Space Center in Houston. (Photo: AP)

1. Houston

% Rise in HNWI: 14%

No. of HNWI : 150,000

Total Wealth (% change): $572 billion (15.2%)

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