2003

7.4

2005

7.4

1993

7.8

1983

8.1

2005

6.2

1990

7.4

1998

7.0

2000

8.2

2005

8.7

2001

7.5

1991

7.8

2005

8.0

2004

7.2

2006

5.2

2006

5.0

1969

7.0

2004

8.1

2006

7.7

1986

5.2

1999

7.8