2000

7.6

2017

6.6

2015

6.7

2006

8.2

2014

7.1

2001

7.6

2016

7.3

1998

7.2

2005

7.2

1993

5.6

2008

6.2

2016

7.1

2013

7.0

1985

7.0

1980

8.6

2013

7.2

1989

8.3

1993

6.3

1995

8.1

2003

7.8