1978

5.7

1994

6.2

1985

5.3

1979

5.0

2002

6.7

1984

4.3

1981

6.1

2004

5.9

1985

6.2

1983

5.2

2000

7.3

1977

6.4

1981

6.7

1985

6.7

1976

6.1

1972

4.5

1982

5.6