1993

6.4

2005

7.2

2012

5.4

2008

5.9

2008

8.9

2004

6.7

2018

5.3

2004

7.3

1996

6.3

1994

6.0

2004

5.9

2016

4.7

2017

6.5

2010

6.2

2007

6.3

2018

7.0

1977

7.2

2004

5.8

2012

5.8

2015

6.8