1960  0     0     0
1961  1 0.627 0.486
1962  2 1.247 0.973
1963  3 1.702 1.323
1964  4 2.408 1.867
1965  5 3.188 2.568
1966  6 3.866 3.022
1967  7 4.201 3.259
1968  8 4.840 3.663
1969  9 5.855 4.321
1970 10 7.625 5.482