2003

6.3

2015

4.3

2009

7.6

2016

7.6

2009

7.3

2020

8.1

1997

7.9

2014

8.5

2014

7.9

2017

7.3

2012

7.8

2015

8.0

2018

7.6

2017

6.8

2000

7.4

1999

8.4

2013

7.2

2013

6.8

1994

8.7

2011

8.3