1964

6.5

2001

8.5

2006

7.4

2014

7.7

2009

7.6

1994

8.7

2006

8.2

1960

8.4

2017

7.5

2001

7.9

2004

8.4

1985

7.7

1997

8.4

1998

7.8

1971

8.2

2007

7.2

1954

8.4

1997

7.9

2014

8.5

1972

8.7