1976

5.5

1983

3.4

1997

7.4

1986

7.5

1953

8.0

1955

7.5

1940

7.9

1983

7.2

1930

7.3

1986

7.8

1972

8.7

1974

8.6

2002

6.7

2005

6.7

1927

8.1

1979

8.3

1982

7.9

2006

6.1

1959

7.8

1931

7.2