1988

7.5

1997

8.3

2004

6.4

1975

6.0

1973

6.3

1954

7.0

1981

6.5

1978

7.2

2001

7.7

2014

6.7

2007

7.8

1983

6.7

2000

7.6

1989

7.0

1979

6.8

1999

6.6

1993

7.5

2006

5.4

1998

6.7

2020

7.3