2011

8.1

2020

7.3

2006

6.4

2009

6.5

2010

4.6

2011

4.5

6.3

1980

6.7

1994

6.9

2012

5.7

2006

7.0

2013

6.2

2013

8.6

1984

7.4

2013

6.5

1967

7.9

2016

4.1

2008

8.0

2003

8.5

1989

8.4