Year

US

Brazil

Canada

China

Total proportion the four

2005

74.78

13.46

7.30

4.40

99.94

2006

79.78

9.34

6.97

3.87

99.96

2007

79.91

8.82

7.34

3.29

99.45

2008

73.54

15.31

8.76

2.32

99.92

2009

71.15

16.81

10.41

1.50

99.88

2010

71.39

16.44

10.74

1.39

99.95

2011

62.12

17.48

11.64

1.44

92.69