2011

8.1

1980

8.4

2009

6.7

1998

7.4

2005

6.8

1972

7.5

2008

7.4

2010

7.7

2016

6.8

2009

7.7

2015

5.9

2009

6.7

2010

7.2

2007

6.9

2005

6.3

2017

8.2

2013

6.2

2014

8.0

2018

7.2

2022

6.8