2006

5.2

2003

4.1

2017

5.7

2016

6.4

2008

6.6

1998

7.1

2007

6.5

2000

6.1

2006

6.0

2005

4.4

2018

5.4

2014

6.1

1974

4.5

1978

4.8

2007

6.2

2005

6.5

1997

6.7

1985

7.0

2014

6.2

2006

7.6