1996

8.2

2013

6.8

1986

5.8

2008

4.7

2019

6.3

1970

7.4

2013

7.0

2012

5.6

2015

7.2

2017

5.2

1989

5.4

2013

8.1

2014

7.6

2011

6.5

2001

5.0

2011

7.2

2016

7.3

2003

5.7

2011

7.0

2010

6.0