1973

7.1

2002

6.1

1989

7.3

2009

5.6

1979

6.7

1940

7.3

1970

6.0

1938

7.0

1966

6.7

2010

6.3

1969

6.9

1970

7.3

1987

6.2

1993

6.5

2021

7.7

2005

5.2

1975

7.3

2007

6.5

2020

5.6

2017

6.2