1973

6.5

1979

4.0

2000

6.0

1995

7.6

1971

6.4

1977

6.8

1987

6.5

1997

6.4

1962

7.0

1963

7.1

1965

6.7

1956

7.5

1974

7.5

2021

6.7

1986

7.6

1993

6.5

2000

6.1

2006

6.7

1926

7.9

2001

7.4