1981

6.6

1980

5.0

1974

7.6

1984

5.9

1989

3.8

1990

4.0

1979

6.0

1976

7.0

1972

7.5

1974

7.0

1984

5.6

1977

4.8

1979

5.0

1978

5.0

1979

3.5