Global Odd Index

The Professional Athlete Index

In this Olympic year, we wanted to understand the statistics behind truly mastering a sport and to celebrate the achievements of the few who do, by calculating the chances of someone being a professional athlete in their country of birth. We then added to the study by calculating where most professionals come from for a range of globally popular sports.

Making it to the top of a sport requires decades of extreme dedication and many thousands of hours of training and practice, which must all be in addition to a complementary set of in-built physical features that mean some people, and not others, have the tools to succeed.

Beyond physical attributes, your country of birth can heavily influence whether the ecosystem is favourable to excelling in a sport. An almost religious love of football across the nation ensures Brazil continues to produce elite footballers by the hundreds, despite limited investment in youth academies in comparison with other countries.

In many places, a sport’s popularity dictates how much financial investment it receives, and these factors combine to facilitate easier progression for budding athletes under the right conditions, or hinder those without.

Make it through these challenges to the upper stratosphere of athletes and you are still at the mercy of injuries or poor form that can limit performance levels and success.

There are obstacles at every turn, meaning only a tiny fraction of amateur sportsmen and women ever turn professional. Here are the probabilities of becoming a professional in a range of globally popular sports around the world.

Football

Number of players per team 11
Current world champions France

It is the world’s most popular sport, the most watched sport, and the sport that connects people across cultures even if they have nothing else in common. Around 250 million people play football globally, attracted by its simplicity and unpredictability. Ahead of the 2015/16 English Premier League season, Leicester City were given odds of 5000/1 to become champions, something they succeeded in doing in one of the greatest sporting shocks of all time. 

Its popularity arguably makes it harder to become a professional, with stiff competition for places restricting opportunities for progression for youngsters with talent. To give an example, there are around 11,000 boys in English football’s youth development system, training regularly at professional clubs. For those entering the system at the age of nine, under 0.5% will ever earn money from football. See below for the odds of becoming a professional footballer in different countries around the world.

Percentage of top tier footballers

This map shows the percentage of current top tier footballers that come from each country.

Country
Percentage of top tier footballers globally
Percentage of top tier footballers globally
Brazil
5.14%
Argentina
4.38%
Nigeria
3.44%
Colombia
3.23%
UK
2.65%
Serbia
2.63%
Saudi Arabia
2.62%
Uruguay
2.60%
Spain
2.47%
Algeria
2.39%
France
2.35%
Peru
1.88%
Czech Republic
1.84%
Netherlands
1.81%
1.79%
Chile
1.75%
India
1.75%
Mexico
1.73%
Ukraine
1.71%
Turkey
1.62%
Ecuador
1.60%
Iran
1.55%
Sweden
1.55%
Bolivia
1.53%
Tunisia
1.51%
Norway
1.50%
Poland
1.47%
Romania
1.47%
South Africa
1.46%
USA
1.42%
Germany
1.42%
Portugal
1.40%
Russia
1.38%
Croatia
1.37%
China
1.36%
Paraguay
1.36%
South Korea
1.35%
Belgium
1.20%
Bulgaria
1.18%
Denmark
1.16%
Iceland
1.13%
Slovakia
1.13%
Austria
1.12%
Italy
1.10%
Costa Rica
1.06%
Australia
1.01%
Hungary
0.99%
Greece
0.98%
Finland
0.90%
Ireland
0.87%
Switzerland
0.81%
Canada
0.69%
Ghana
0.61%
Bosnia
0.50%
Senegal
0.46%
Ivory Coast
0.42%
Cameroon
0.37%
Morocco
0.33%
Montenegro
0.25%
Slovenia
0.23%
Macedonia
0.19%
Albania
0.18%
Georgia
0.16%
New Zealand
0.14%
Israel
0.12%
Panama
0.09%
Jamaica
0.08%
Egypt
0.07%
Moldova
0.07%
Belarus
0.06%
Luxembourg
0.06%
Trinidad & Tobago
0.06%
Estonia
0.05%
Latvia
0.05%
Uzbekistan
0.04%
Haiti
0.04%
Kenya
0.04%
Lithuania
0.04%
Cyprus
0.03%
Kazakhstan
0.03%
Indonesia
0.02%
Malaysia
0.02%
Namibia
0.02%
El Salvador
0.02%
Thailand
0.02%
Cuba
0.01%
Dominican Republic
0.01%
Ethiopia
0.01%
Guatemala
0.01%
Hong Kong
0.01%
Puerto Rico
0.01%
Taiwan
0.01%
Bahamas
0.00%
Barbados
0.00%
Vietnam
0.00%
Philippines
0.00%
Afghanistan
%
Angola
%
Armenia
%
Azerbaijan
%
Bangladesh
%
Belize
%
Benin
%
Bhutan
%
Botswana
%
Brunei Darussalam
%
Burkina Faso
%
BDI
%
Cambodia
%
Central African Republic
%
Chad
%
Democratic Republic of the Congo
%
Djibouti
%
East Timor
%
Equatorial Guinea
%
Eritrea
%
Fiji
%
French Southern and Antarctic Lands
%
Gabon
%
Gambia
%
Greenland
%
Guinea
%
Guinea Bissau
%
Guyana
-%
Honduras
%
Iran
%
Iraq
%
Jordan
%
Kuwait
%
Kosovo
%
Kyrgyzstan
%
Laos
%
Lebanon
%
Lesotho
%
Liberia
%
Libya
%
Madagascar
%
Malawi
%
Mali
%
Mauritania
%
Mongolia
%
Mozambique
%
Myanmar
%
Nepal
%
New Caledonia
%
Nicaragua
%
Niger
%
North Korea
%
Northern Cyprus
%
Oman
%
Pakistan
%
Papua New Guinea
%
Qatar
%
Republic of the Congo
%
Rwanda
%
Sierra Leone
%
Solomon Islands
%
Somalia
%
South Sudan
%
Sri Lanka
%
Somaliland
%
Sudan
%
Suriname
-%
Swaziland
%
Syria
%
Tajikistan
%
Tanzania
%
Togo
%
Turkmenistan
%
Uganda
%
United Arab Emirates
%
Vanuatu
%
West Bank
%
Venezuela
%
Western Sahara
%
Yemen
%
Zambia
%
Zimbabwe
%
Falkland Islands
%
Odds of being a top tier footballer (1:X)

This map reveals the odds of being a top tier footballer in each country, ranked in order of probability. It shows that 1 in every 83 men born in Iceland in the study’s age bracket are top tier footballers, the best odds in the world.

Country
Odds of being a top tier footballer (1:X)
Odds of being a top tier footballer (1:X)
Iceland
82
Montenegro
258
Uruguay
451
Serbia
546
Norway
777
Croatia
802
Slovakia
1075
Finland
1166
Czech Republic
1276
Denmark
1343
Bosnia
1421
Costa Rica
1440
Bulgaria
1470
Sweden
1528
Austria
1770
Peru
1880
Portugal
1889
Slovenia
1924
Luxembourg
1949
Ireland
2236
Belgium
2260
Switzerland
2298
Paraguay
2400
Greece
2445
Hungary
2504
Netherlands
2539
Tunisia
2814
Senegal
3136
Macedonia
3207
Namibia
3236
Chile
3512
Argentina
3626
Spain
3677
Bolivia
3731
Algeria
3741
Romania
3766
Ecuador
4508
Saudi Arabia
4866
Albania
5150
Jamaica
5348
Australia
5838
Colombia
6284
UK
6357
Ukraine
6365
Georgia
6658
Estonia
6705
Poland
6753
Cyprus
6970
France
7363
Trinidad & Tobago
7947
New Zealand
9312
Turkey
10007
Canada
10185
Iran
10605
Italy
11529
Latvia
11713
Germany
12667
Moldova
12783
15420
Brazil
15713
Barbados
15738
Panama
16006
South Africa
16240
South Korea
17910
Lithuania
22121
Russia
23401
Israel
23842
Ghana
24528
Mexico
31220
Nigeria
32622
Ivory Coast
33589
Cameroon
37325
Morocco
38972
Belarus
40136
USA
55393
El Salvador
143837
Haiti
157673
Kazakhstan
176816
Puerto Rico
186458
Hong Kong
200741
Cuba
252405
Uzbekistan
300588
China
319615
India
360494
Guatemala
572193
Egypt
589345
Taiwan
639736
Dominican Republic
686706
Kenya
701467
Malaysia
704705
Thailand
1050249
Indonesia
4981770
Philippines
6098472
Ethiopia
8842898
  • Football

  • Ice Hockey

  • Basketball

  • Tennis

  • MMA

  • Golf

  • Athletics

  • Cycling

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International Results
Percentage of top tier athletes globally Odds of being a top tier athlete (1:X)
# Country Country Code
13 Guyana GUY - - - - 0.27 - - - - - - - 130,535.50 - - -
52 Suriname SUR - - - - 0.27 - - - - - - - 63,939.00 - - -
69 Albania ALB 0.18 0.00 0.01 0.00 0.00 0.00 0.03 0.30 5150 - 272912 - - - 38988 45486
70 Argentina ARG 4.38 0.00 3.77 3.76 0.53 0.90 0.35 0.10 3626 - 13198 42552 2276485 267823 57634 2276485
71 Australia AUS 1.01 1.57 1.26 1.26 1.59 6.27 2.59 2.40 5838 12356 14719 21983 282104.83 14225 2894 35264
72 Austria AUT 1.12 0.72 1.10 1.26 0.53 0.69 0.36 1.15 1770 9015 5624 15776 283946.50 43685 7012 24692
73 Belgium BEL 1.20 0.76 1.43 1.54 0.00 0.26 0.91 7.00 2260 11809 5950 17713 - 155862 3784 5567
74 Bulgaria BGR 1.18 1.23 0.07 0.88 0.53 0.00 0.27 0.70 1470 4670 83268 19985 249802 - 8191 35687
75 Bahamas BHS 0.00 0.00 0.08 0.11 0.00 0.00 0.33 0.00 - - 5326 12427 - - 505 -
76 Bosnia BIH 0.50 0.00 0.75 0.35 0.27 0.00 0.08 0.45 1421 - 2964 20443 204417 - 10760 22714
77 Belarus BLR 0.06 2.31 0.20 0.63 0.27 0.00 0.79 0.85 40136 3379 37907 37907 682304 - 3834 40136
78 Bolivia BOL 1.53 0.00 0.00 0.42 0.00 0.00 0.08 0.00 3731 - - 136452 - - 86181 -
79 Brazil BRA 5.14 0.00 2.77 2.07 13.79 0.16 1.29 0.00 15713 - 91301 393057 445968.14 7730098 79420 -
80 Barbados BRB 0.00 0.00 0.01 0.04 0.00 0.00 0.18 0.00 15738 - 15738 15738 - - 394 -
81 Canada CAN 0.69 11.36 1.39 1.37 1.86 1.21 1.86 0.70 10185 2036 15878 51703 288053.86 87669 4802 144027
82 Switzerland CHE 0.81 2.23 0.14 1.47 0.53 0.53 0.90 2.00 2298 2734 40993 12689 266448.50 53291 2626 13323
83 Chile CHL 1.75 0.00 0.07 0.70 0.00 0.42 0.20 0.00 3512 - 293170 87952 - 219878 38240 -
84 China CHN 1.36 0.01 3.92 1.58 0.80 2.16 3.30 0.00 319615 124649428 347214 2769988 41549810 3040231 167091 -
85 Ivory Coast CIV 0.42 0.00 0.14 0.04 0.00 0.00 0.04 0.10 33589 - 312631 4064197 - - 508025 2032099
86 South Africa ZAF 1.46 0.00 0.01 0.77 0.27 7.80 1.41 1.05 16240 - 6820247 310012 6820247 46084 21314 324775
87 Vietnam VNM 0.00 0.00 0.00 0.11 0.00 0.00 0.10 0.00 - - - 1007298 - - 137360 -
88 Cameroon CMR 0.37 0.00 0.11 0.00 0.27 0.00 0.09 0.20 37325 - 395634 - 3956335 - 197818 989085
89 Colombia COL 3.23 0.00 0.09 0.81 0.00 0.42 0.42 3.85 6284 - 727244 252955 - 727244 61894 75559
90 Costa Rica CRI 1.06 0.00 0.00 0.04 0.00 0.00 0.08 0.10 1440 - - 437383 - - 23021 218692
91 Uzbekistan UZB 0.04 0.00 0.00 0.60 0.27 0.00 0.20 0.15 300588 - - 194499 3306461 - 71881 1102154
92 Cuba CUB 0.01 0.00 0.13 0.07 0.00 0.00 0.39 0.05 252405 - 84136 504808 - - 11345 1009615
93 Cyprus CYP 0.03 0.00 0.13 0.14 0.00 0.00 0.19 0.05 6970 - 5228 15681 - - 1494 62719
94 USA USA 1.42 5.66 26.42 9.59 38.73 23.09 21.99 2.25 55393 45526 9298 82379 154037.08 51346 4520 499762
95 Czech Republic CZE 1.84 5.69 1.96 2.00 0.80 0.32 1.15 1.30 1276 1355 3761 11810 224377 112189 2590 25891
96 Germany DEU 1.42 1.09 1.81 4.53 0.53 2.48 2.95 3.25 12667 54399 31133 40062 2583925.50 109955 7737 79506
97 Denmark DNK 1.16 2.46 0.17 0.21 0.53 2.00 0.44 2.45 1343 2073 27845 74253 222756.50 11725 4501 9093
98 Uruguay URY 2.60 0.00 0.17 0.32 0.00 0.00 0.06 0.55 451 - 20984 37304 - - 25826 30522
99 Dominican Republic DOM 0.01 0.00 0.42 0.35 0.00 0.05 0.05 0.00 686706 - 36143 137342 - 1373411 57226 -
100 Algeria DZA 2.39 0.00 0.00 0.11 0.00 0.00 0.24 0.30 3741 - - 856456 - - 47582 428228
101 Ecuador ECU 1.60 0.00 0.01 0.42 0.27 0.00 0.22 0.85 4508 - 2073173 172765 2073173 - 42311 121952
102 Egypt EGY 0.07 0.00 0.01 0.67 0.00 0.00 0.19 0.05 589345 - 11197542 589345 - - 260409 11197542
103 Spain ESP 2.47 1.32 1.28 4.78 0.53 2.16 2.95 5.20 3677 22632 22245 19138 1301294.50 63479 3897 25026
104 Estonia EST 0.05 1.05 0.99 0.42 0.00 0.05 0.39 0.90 6705 1021 1032 7822 - 93853 1068 5215
105 Ethiopia ETH 0.01 0.00 0.00 0.00 0.00 0.00 1.81 0.60 8842898 - - - - - 43243 1473817
106 Finland FIN 0.90 6.93 1.30 0.63 0.00 0.90 1.16 0.70 1166 498 2527 16699 - 17681 1144 21470
107 France FRA 2.35 2.37 2.02 6.53 0.80 3.64 3.38 7.65 7363 23936 26783 26639 1651535.67 71807 6486 32384
108 UK GBR 2.65 1.01 1.05 3.58 3.18 10.17 3.93 2.60 6357 54821 50253 47297` 402013.25 24997 5421 92773
109 Georgia GEO 0.16 0.64 0.64 0.28 1.06 0.00 0.04 0.30 6658 5469 2375 38278 76554.75 - 34025 51037
110 Ghana GHA 0.61 0.00 0.01 0.25 0.00 0.00 0.13 0.00 24528 - 4292264 613181 - - 143076 -
111 Greece GRC 0.98 0.00 1.41 0.60 0.00 0.05 0.77 0.70 2445 - 5325 40399 - 686768 3925 49056
112 Guatemala GTM 0.01 0.00 0.00 0.04 0.00 0.05 0.11 0.55 572193 - - 1716578 - 1716578 68664 156053
113 Hong Kong HKG 0.01 0.00 0.01 0.28 0.00 0.16 0.06 0.00 200741 - 401480 50186 - 133827 30884 -
114 Croatia HRV 1.37 1.48 1.23 1.30 0.00 0.00 0.33 0.70 802 2442 2787 8510 - - 4199 22490
115 Haiti HTI 0.04 0.00 0.03 0.04 0.27 0.00 0.02 0.00 157673 - 578130 1734389 1734389 - 346879 -
116 Hungary HUN 0.99 2.31 1.69 0.70 0.27 0.00 0.71 0.85 2504 3508 4571 35421 708405 - 4401 41672
117 Indonesia IDN 0.02 0.00 0.00 0.18 0.00 0.21 0.06 0.00 4981770 - - 5978123 - 7472654 2135045 -
118 India IND 1.75 0.00 0.00 2.28 0.00 2.64 1.07 0.00 360494 - - 2778570 - 3612141 743240 -
119 Ireland IRL 0.87 0.00 0.00 0.21 0.53 0.79 0.86 0.40 2236 - - 93133 279396 37254 2867 69850
120 Iran IRN 1.55 0.00 1.40 0.14 0.27 0.00 0.22 0.40 10605 - 36782 1176999 4707991 - 96082 588500
121 Iceland ISL 1.13 0.78 0.07 0.00 0.00 0.16 0.12 0.60 82 388 4381 - - 8762 940 2191
122 Israel ISR 0.12 1.02 1.43 0.95 0.00 0.00 0.30 0.65 23842 9377 6371 30906 - - 12094 64188
123 Italy ITA 1.10 1.90 1.66 7.13 0.27 1.53 2.59 9.30 11529 21877 23892 17890 3631378 125221 6208 19525
124 Jamaica JAM 0.08 0.00 0.08 0.04 0.53 0.00 1.90 0.00 5348 - 17570 122984 61492.50 - 286 -
125 Japan JPN 1.79 0.54 2.57 3.05 1.06 7.96 7.84 0.65 15420 168958 33792 91277 1985246 52590 4477 610846
126 Kazakhstan KAZ 0.03 1.02 0.10 0.56 0.53 0.00 0.28 0.90 176816 19868 196462 110510 884076 - 27628 98232
127 South Korea KOR 1.35 0.30 1.76 1.23 1.59 6.91 0.51 0.00 17910 267261 43161 198537 1158126.83 53045 59904 -
128 Kenya KEN 0.04 0.00 0.03 0.14 0.00 0.05 4.32 0.05 701467 - 2572044 1929033 - 7716130 7899 7716130
129 Lithuania LTU 0.04 1.39 2.14 0.46 0.27 0.00 0.00 0.55 22121 2195 1355 20420 265446 - 3124 24132
130 Luxembourg LUX 0.06 0.00 1.63 0.07 0.00 0.00 0.07 0.80 1949 - 210 15589 - - 1949 1949
131 Latvia LVA 0.05 1.15 1.50 0.28 0.27 0.00 0.27 0.55 11713 1524 1112 19033 152256 - 2457 13842
132 Morocco MAR 0.33 0.00 0.02 0.49 0.00 0.11 0.95 0.15 38972 - 1831653 261666 - 1831653 16961 1221102
133 Moldova MDA 0.07 0.00 0.01 0.18 0.80 0.00 0.08 0.00 12783 - 268418 53684 89473.33 - 15790 -
134 Mexico MEX 1.73 0.80 0.95 0.91 0.27 0.47 0.63 0.75 31220 220764 177626 594362 15453390.50 1717044 108067 1030227
135 Macedonia MKD 0.19 0.00 0.12 0.21 0.00 0.00 0.00 0.45 3207 - 15741 28858 - - - 19239
136 Montenegro MNE 0.25 0.00 2.57 0.00 0.00 0.00 0.03 0.45 258 - 79 - - - 2604 2026
137 Malaysia MYS 0.02 0.00 0.00 0.11 0.00 0.58 0.14 0.10 704705 - - 1174508 - 320321 113663 1761762
138 Namibia NAM 0.02 0.00 0.00 0.04 0.00 0.00 0.08 0.55 3236 - - 22644 - - 1259 2059
139 Nigeria NGA 3.44 3.44 0.39 0.18 0.27 0.00 0.69 0.00 32622 - 893462 6432923 32164612 - 204871 -
140 Netherlands NLD 1.81 0.85 0.25 2.18 0.80 0.79 1.21 5.65 2539 17802 57275 21248 439098.33 87820 4826 11658
141 Norway NOR 1.50 2.48 0.00 0.25 0.27 0.63 0.71 1.95 777 1542 - 47549 332834 27737 2068 8535
142 New Zealand NZL 0.14 1.47 1.74 0.46 1.06 0.90 0.64 2.80 9312 2983 2402 29367 95440.50 22457 2652 6818
143 Panama PAN 0.09 0.00 0.04 0.00 0.00 0.00 0.05 0.60 16006 - 104032 - - - 37830 34678
144 Peru PER 1.88 1.88 0.01 0.53 0.00 0.00 0.19 0.00 1880 - 1011166 67412 - - 23516 -
145 Philippines PHL 0.00 0.00 1.85 0.21 0.27 0.32 0.08 0.00 6098472 - 36087 1016413 6098472 1016413 338805 -
146 Poland POL 1.47 0.26 2.34 1.30 3.18 0.11 1.91 1.85 6753 123890 13316 77013 237455.25 1424727 6597 77013
147 Puerto Rico PRI 0.01 0.00 0.83 0.04 0.00 0.05 0.24 0.50 186458 - 4908 372915 - 372915 6781 37292
149 Portugal PRT 1.40 0.00 0.01 1.16 0.00 0.47 0.87 1.45 1889 - 760961 23060 - 84552 3883 26241
151 Paraguay PRY 1.36 0.00 0.02 0.07 0.27 0.05 0.03 0.00 2400 - 467812 467812 935623.50 935624 133661 -
153 Romania ROU 1.47 0.72 0.01 1.79 0.00 0.00 0.49 0.05 3766 25220 1588807 31154 - - 14187 1588807
155 Russia RUS 1.38 17.30 1.17 3.65 13.53 0.00 2.01 2.20 23401 6153 86821 89325 182152.59 - 20463 211131
157 Saudi Arabia SAU 2.62 0.00 0.00 0.00 0.00 0.00 0.07 0.60 4866 - - - - - 228960 305280
159 Senegal SEN 0.46 0.00 0.45 0.00 0.00 0.00 0.06 0.00 3136 - 10094 - - - 31833 -
161 El Salvador SLV 0.02 0.00 0.01 0.07 0.00 0.00 0.02 0.60 143837 - 1006852 503427 - - 251714 83905
163 Serbia SRB 2.63 0.76 3.41 1.47 0.27 0.00 0.30 0.65 546 6233 1319 9794 411314 - 6050 31640
165 Slovakia SVK 1.13 4.74 0.16 1.23 0.00 0.05 0.25 0.65 1075 839 23135 9916 - 347011 6089 26694
167 Slovenia SVN 0.23 2.58 2.06 0.46 0.00 0.00 0.35 0.90 1924 557 662 9617 - - 1583 6946
169 Sweden SWE 1.55 6.21 0.20 1.40 1.33 4.38 1.16 0.70 1528 1252 37670 16952 135609.20 8170 2579 48433
171 Thailand THA 0.02 0.00 0.00 0.81 0.00 3.37 0.11 0.55 1050249 - - 273979 - 98462 242366 572864
173 Trinidad & Tobago TTO 0.06 0.00 0.02 0.00 0.00 0.00 0.30 0.00 7947 - 63566 - - - 1898 -
174 Tunisia TUN 1.51 0.00 0.13 0.39 0.00 0.00 0.09 0.00 2814 - 101725 110972 - - 61035 -
175 Turkey TUR 1.62 0.00 1.81 0.81 0.00 0.00 0.84 0.55 10007 - 27970 201865 - - 24309 422079
177 Taiwan TWN 0.01 0.00 0.00 0.74 0.00 0.79 0.37 0.00 639736 - - 91392 - 127948 22849 -
178 Ukraine UKR 1.71 1.51 1.57 1.62 0.80 0.00 1.22 0.80 6365 23721 21745 68068 1043698.33 - 11387 195694

Methodology

The Professional Athlete Index analyses eight globally popular team and individual sports. For each sport, a list of top tier male competitors from the latest completed season or ranking was gathered.

For team sports, player data was taken from every team playing in the top domestic league of the world’s 35 highest ranked nations. For individual sports, the players that feature in each sport’s international association ranking were included.

The athletes were assigned to countries based on their nationality. In cases of multiple nationalities, the athletes were assigned to their country of birth.

To calculate the odds of being a top tier athlete, we compared the number of top tier athletes from each country with that country’s number of births over a 12-year period – representing a typical length of a sporting career at the top level. The odds represent the chances of someone born during that period making it to the elite level of each sport.

  • Percentage of top tier athletes

    This percentage was calculated using the following equation:
    Total number of top tier athletes from each country / Total number of top tier athletes in each sport

  • Odds of being a top tier athlete (1:X)

    The odds were calculated for each country in the study using the following equation:

    1 / (number of top tier athletes from each country / total number of people born in each country over 12-year period) / (number of people born over 12-year period in each country that are not currently top tier athletes / total number of people born in each country over 12-year period)

     

    Source: Male births, years 1991 to 2003, UN Demographic Yearbook.

Sport-Specific Methodology Notes