1993

6.8

1989

7.2

2002

5.3

2006

3.0

2005

5.2

1997

6.3

1998

5.7

1987

8.3

2006

6.6

2005

4.5

2004

5.2

2003

6.2

2002

4.4

2002

4.3

2002

3.9

1998

7.8

1997

6.2

1995

6.0

1993

7.7

1992

7.6