2009

4.9

2005

4.3

2002

6.2

2001

5.1

1994

5.8

2003

6.1

1975

1.0

2005

6.2

2003

6.2

2005

5.5

2006

5.5

2007

5.7

2002

3.9

2008

6.2

2006

6.0

2002

6.3

2003

6.8

2000

6.2

2001

6.6

2002

5.3