1973

7.3

1961

7.2

2010

7.8

1997

7.9

1995

8.0

1951

7.2

1996

8.0

2002

7.1

2008

8.1

1999

8.0

2015

7.9

1959

6.9

1953

7.2

1999

6.6

1977

8.2

1938

7.1

1994

7.0

1998

8.1

1985

7.7

2006

6.6