1940

5.7

1950

6.9

1975

5.9

1973

6.7

2021

6.3

1980

5.9

1930

5.3

1970

6.0

1972

4.9

2017

6.0

1992

5.3

1964

5.8

2008

4.4

2004

6.3

2009

5.9

2001

4.5

1987

6.3

2005

6.3

2000

5.2

2003

3.9