2005

2.3

2001

6.3

1998

5.7

2004

7.2

1997

6.3

1998

6.9

1996

6.6

1992

6.2

2006

3.0

2005

5.2

2005

3.6

1987

7.6

1986

7.5

1993

6.8

1989

7.2

1988

7.8

1997

7.5

1986

5.4

1995

6.0

1994

6.4