2006

6.1

2005

8.8

2000

6.2

1987

7.3

1986

4.0

1983

5.2

2001

8.1

1999

7.6

2005

7.4

2002

8.2

2006

7.1

1992

7.1

1990

7.1

2007

4.0

1999

7.1

6.7

1993

7.7

1997

6.8

1992

6.8

2005

5.0