2011

3.9

1996

4.6

2006

5.4

2005

6.9

1989

3.4

2003

9.0

1992

7.0

1995

3.5

2003

0.0

2002

4.3

2014

7.9

2009

4.6

2007

0.0

2016

0.0

2006

6.7

1999

4.5

2008

4.7

2018

4.0