1992

6.8

2007

8.2

2009

8.7

2020

8.0

2006

8.5

2007

7.5

2016

7.2

2011

7.5

2012

7.4

2015

8.4

1995

8.6

2005

8.0

2017

8.1

2009

8.1

2014

8.6

2012

6.7

1990

6.9

1998

7.5

2017

8.4