2009

5.8

2002

5.0

2003

2.9

1993

5.5

1986

5.0

1973

3.7

1975

5.8

2005

3.7

1992

6.0

1985

3.8

2006

5.2

1999

5.2

1999

4.3

2005

5.8

1996

4.6

1997

4.7

1970

4.2

1973

6.4

2002

5.3

1988

5.4