2006

5.1

1976

5.6

2004

4.9

2001

4.5

2006

5.3

2000

6.1

2008

5.2

1983

6.2

1986

6.0

1962

5.6

2017

7.0

2020

6.9

1966

7.6

2009

7.3

2009

6.6

1990

6.5

1991

5.3

2001

6.6

1990

6.2

1947

6.8