2003

6.0

1991

4.0

2005

4.8

2008

5.7

1994

5.8

2003

6.1

2003

5.7

1976

6.7

2005

6.5

1973

6.9

1982

2.7

1999

3.2

1990

6.8

2003

1.8

2004

5.5

2005

6.3

2002

5.2

2001

5.0

2005

5.8

1969

3.8