2011

6.5

1999

5.7

1986

7.0

2002

6.4

2000

5.0

2005

6.1

2003

8.7

2002

5.2

2006

6.9

2001

5.4

2004

6.0

2008

7.5

1975

7.3

1998

5.4

1999

4.5

2002

6.7

2009

5.5

2008

5.6

1972

7.4

2007

6.7