1997

9.0

1976

0.0

1979

10.0

1989

6.5

1995

8.7

1991

7.5

2006

8.2

1994

7.8

1990

7.0

2001

7.1

1980

7.9

1996

6.0

1988

7.0

1999

8.3

2005

6.5