1983

8.2

1993

6.6

1946

7.6

2006

6.9

2001

8.0

2007

6.7

2005

6.1

2003

6.6

1967

6.9

2004

7.4

1976

7.0

1963

7.7

2006

6.3

2001

6.5

2003

6.3

1988

6.9

2004

6.4

2016

4.8

1987

6.3

2006

0.0