1971

4.7

1968

5.0

1969

2.8

1972

3.0

1968

0.0

1978

5.2

1973

5.3

1977

5.6

1983

4.8

1976

6.1

1981

7.9

1960

6.5

1977

6.1

1978

6.1

1977

6.8

1967

5.4