1984

6.5

2002

4.2

1999

7.5

1989

6.6

1996

6.4

2006

6.9

1984

7.0

2000

6.4

2005

6.5

2001

7.0

2001

6.7

2005

5.8

1990

6.9

2005

6.4

2002

7.0

1993

8.2

2005

8.1

2000

0.0

1992

6.5

2007

10.0