1950

8.0

1996

7.6

1971

8.2

1983

7.2

1991

8.1

1954

6.0

1986

6.0

1949

7.4

1989

7.5

1996

6.5

2001

6.9

2001

7.1

1992

3.8

1944

2.7

2001

6.6

1983

5.2

1937

7.0

1956

7.3

1953

3.3

2002

5.8