1959

5.7

1968

7.1

1970

6.4

1967

6.9

1951

6.5

1973

6.9

1962

6.7

1958

6.5

1976

7.5

1981

6.7

1972

5.4

1967

5.3

1969

6.7

1958

5.0

1960

0.0