Countries/Regions

Number of papers

Proportion

Cumulative ratio

America

10,903

52.81%

52.81%

Britain

1694

8.21%

61.01%

Australia

1384

6.70%

67.72%

Holland

925

4.48%

72.20%

Canada

730

3.54%

75.73%

Germany

631

3.06%

78.79%

Spain

598

2.90%

81.68%

China (including Hong Kong, Macao)

586

2.84%

84.52%

Korea

490

2.37%

86.89%

Belgium

376

1.82%

88.72%