1940

6.9

1969

5.4

1949

7.3

2009

6.0

2019

6.9

1947

7.5

1932

4.0

1985

6.7

1981

6.5

1996

6.9

2001

6.7

2003

6.1

2000

7.6

2006

7.4

1997

6.7

2005

6.5

1987

7.3

1998

6.8

1998

7.3

2000

6.3