1974

7.3

1999

8.2

2012

7.8

2017

6.1

2010

8.4

2021

7.1

2017

7.4

2006

5.5

2016

5.9

2016

6.1

2018

6.6

2019

8.1

2006

7.9

2004

6.6

2010

6.4

2010

7.7

2010

6.8

2014

8.0

2011

7.1

2007

6.6