1984

7.5

1991

6.4

1977

6.0

1971

7.6

1976

7.0

1982

7.2

1993

7.1

1978

7.1

1977

6.8

2005

0.0

1999

7.9

1991

7.0

1975

5.9

1997

6.2

1987

6.0

1972

7.3

2004

6.5

1990

7.4

1989

6.4

1998

7.8