1976 6.8

1976 5.5

1975 6.9

1975 6.4

1975 8.1

1974 7.3

1974 6.7

1973 6.7

1973 6.7

1973 7.8

1973 7.1

1973 7.6

1973 6.4

1973 7.0

1972 7.1

1972 6.8

1972 7.2

1971 7.2

1971 6.9

1971 6.5