2003

6.5

1997

7.2

2002

6.4

2002

6.6

2001

6.1

2006

6.6

1983

4.1

1996

7.0

2004

6.3

2006

6.5

2005

7.0

1990

5.1

1986

4.4

1990

6.0

1979

5.0

1997

5.2

2006

4.3

1985

7.5

2001

7.0

1993

8.1