1976

3.6

1979

6.1

1980

5.7

1984

5.6

1981

5.8

1984

6.1

1982

6.0

1982

6.1

1978

5.4

1972

5.2

1975

4.8

1976

4.6

1979

5.2

1977

5.4

1975

4.9

1978

5.1

1977

2.5

1992

4.1

1979

4.8

1989

6.5

1976

6.5

1976

6.2

1977

6.4

1951

0.0

1980

6.1