1985

3.2

1976

3.3

1979

2.0

2005

5.2

1973

6.4

2008

2.5

2002

4.2

1980

5.3

1993

6.2

2009

6.6

2012

0.0

1999

5.3

2002

5.1

1973

4.6

1998

4.0

1982

5.2

2009

2.7

1997

4.0

2007

2.8

1997

1.0