1997

8.1

2006

7.9

2004

8.6

1998

7.2

2004

8.3

5.8

1987

8.4

2013

7.2

2015

7.3

2019

7.7

1999

7.9

2012

6.8

2001

7.6

2003

8.2

1996

5.3

2014

7.0

2016

6.9

2015

6.1

2013

7.8

2014

7.8