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Which country has the largest stock of brilliant people ? The answer to this question depends in part on raw brainpower, but also on the size of a country.

Exclusively for Business Insider, Dr. Jonathan Wai , a Duke University Talent Identification Program research scientist and psychologist, compiled a new ranking of countries based on scores on the 2009 PISA assessment , which tests reading, math, and science competency in 15-year-olds.

Multiple researchers have found that these tests, administered by the Organization for Economic Cooperation and Development (OECD), are a good measure of "g," or general intelligence.

In our list, the rank order is based on two things. First, we identified the average percentage of teenagers in each country who achieved the top score of six on math or verbal tests (globally, around the 98th percentile). Second, we cross-referenced this percentage with population to estimate the number of brilliant people per country.

This provides a new way of looking at the raw brainpower of each country, not counting the significant effects of immigration and emigration.

If you looked only at average scores, you’d find the U.S. is only ranked 24th, near the middle of the pack. But if you then take into account the high-scoring right tail and population, the U.S. is not doing so bad.

Note that we're not including China on this list. Not every student in China was assessed, but only a few cities. And the result was that Shanghai in particular was a large outlier. Shanghai represents a tiny fraction of China's population, is a migration hub that attracts elites, and is much wealthier than the country as a whole. 84% of Shanghai's high school students go to college, while 24% do nationwide. Parents in Shanghai also spend a great deal of money on external tutoring, which an average worker couldn't afford.

It's not representative of China as a whole.

If Shanghai were included on its own, it would rank third on this list. If the scores in China as a whole were even near the international average, the country as a whole would rank first, given the sheer size of the population.

Below are the countries with the most brain power, noting the average percentage getting the top score on PISA tests, and the the estimated number of brilliant people.

#1 The United States

On average, 1.7% scored at elite levels

5,336,300 brilliant people estimated

#2 Japan

On average, 4.05% scored at elite levels

5,167,800 brilliant people estimated

#3 South Korea

On average, 4.40% scored at elite levels

2,200,000 brilliant people estimated

#4 Germany

On average, 2.60% scored at elite levels

2,129,140 brilliant people estimated

#5 France

On average, 2.20 % scored at elite levels

1,445,400 brilliant people estimated

#6 Taiwan

On average, 5.85 % scored at elite levels

1,365,390 brilliant people estimated

#7 Canada

On average, 3.10 % scored at elite levels

1,081,280 brilliant people estimated

#8 Russia

On average, 0.65% scored at elite levels

932,750 brilliant people estimated

#9 The United Kingdom

On average, 1.4% scored at elite levels

885,220 brilliant people estimated

#10 Australia

On average, 3.3 % scored at elite levels

748,440 brilliant people estimated

#11 Italy

On average, 1% scored at elite levels

609,200 brilliant people estimated

#12 Poland

On average, 1.45% scored at elite levels

558,830 brilliant people estimated

#13 Singapore

On average, 9.10% scored at elite levels

483,392 brilliant people estimated

#14 Turkey

On average, 0.65 % scored at elite levels

481,000 brilliant people estimated

#15 Hong Kong

On average, 6.00% scored at elite levels

429,300 brilliant people estimated

#16 The Netherlands

On average, 2.55% scored at elite levels

427,635 brilliant people estimated

#17 Belgium

On average, 3.45% scored at elite levels

384,330 brilliant people estimated

#18 Spain

On average, 0.75% scored at elite levels

354,525 brilliant people estimated

Average score ranking: 35