1997

5.2

2008

6.1

2006

5.0

2011

6.7

2012

5.9

1994

7.6

1997

6.8

2003

5.7

1996

6.2

2004

4.9

2013

7.1

2004

5.3

2005

5.2

1999

6.0

2002

7.9

2001

6.5

2009

6.3

2000

6.3

2002

6.8

2007

6.9

2013

6.2

2006

4.0