1990

6.1

1951

6.4

1976

7.5

2004

6.7

1992

6.7

1988

6.1

1983

6.5

1987

5.3

1999

5.7

1935

7.5

1987

5.5

1996

5.8

2002

6.3

1952

6.7

2010

5.8

2001

6.4

2004

5.7

1993

5.8

1977

6.5

1969

5.9