1964

6.9

2008

8.7

1976

7.5

1991

5.3

1972

6.9

2003

5.0

1938

7.1

1967

5.6

2007

7.4

2010

6.9

2005

6.4

1984

7.2

1998

6.1

1997

6.1

1982

6.0

1995

5.5

1949

6.8

1946

6.8

1939

7.3

1950

7.1