1996

7.7

1999

7.4

2002

8.4

1989

8.6

1989

8.3

2013

7.2

2010

8.2

2015

8.2

2004

8.6

2013

8.1

1996

5.4

1997

8.3

2003

7.6

2009

8.2

2005

7.3

2015

7.7

2014

6.0

1989

7.2

2018

7.9

2010

8.5