1975

6.9

1980

6.9

1981

6.2

1973

6.3

1977

6.8

1976

4.1

1977

6.0

1977

6.5

1983

4.1

1975

6.7

1971

6.6

1972

6.7

1978

6.1

1972

5.6

1979

6.7

1968

6.3

1969

7.1

1974

6.5

1982

6.3

1977

6.9

1976

6.5

1975

5.5

1978

5.7

1972

6.9

1982

6.0

1984

6.7

1969

6.6

1978

6.0

1974

6.4

1982

6.7

1974

5.8

1978

6.4

1978

6.1

1972

5.6

1971

5.8

1972

6.8

1970

6.3

1980

5.5

1971

6.0

1972

6.2

1973

6.7

1971

6.9

1981

6.7

1981

5.7

1969

5.9

1970

6.7

1969

6.6

1979

6.4

1974

5.9

1976

6.7

1973

3.5

1966

6.5

1976

5.3

1973

6.4

1979

6.2

1974

6.3

1977

6.5

1974

5.3

1975

6.0

1967

5.8

1970

6.8

1978

6.5

1973

3.0

1978

7.0

1972

6.7

1976

6.4

1979

7.0

1970

6.2

1974

5.0