1970

8.2

1972

6.6

1952

7.8

1957

7.9

1961

7.8

1969

7.1

1970

7.1

1956

7.9

1935

7.5

1993

6.8

1987

6.5

1996

6.0

1965

8.1

1974

7.0

2006

6.0

1966

6.9

2012

6.4

2001

7.6

1954

7.5

2007

7.0