1955

7.0

1971

6.0

1972

5.0

1972

4.8

1973

4.3

1975

4.7

1956

6.8

1962

7.3

1966

5.0

1958

6.5

1957

6.2

1956

6.2

1959

5.8

1961

5.1

1976

4.2

1954

6.6

1967

6.2

1967

4.8

1964

4.2

1957

4.0

1965

5.6

1961

6.5

1956

6.0

1963

6.5

1960

3.5

1970

4.8

1958

7.0

1958

6.1

1967

6.7