1972

8.6

1966

7.3

1964

7.9

1971

8.1

1975

7.4

1972

5.7

1967

6.8

1973

7.0

1977

6.3

1966

6.1

1973

4.9

1972

6.7

1962

6.2

1963

5.6

1974

5.7

1972

0.0