1997

6.7

1971

6.7

1964

7.8

1964

7.1

1991

8.3

1946

7.8

1955

7.3

2002

6.7

1997

6.9

2002

5.4

2001

6.0

1997

6.0

1996

5.6

1991

6.1

1993

6.3

1988

5.9

2000

6.1

1983

6.5

1983

6.0

1937

6.7