in general , the levels went like this : a1 = elite male ( top 5 % sin score ) , married a2 = elite female ( top 5 % sin score ) , married a3 = elite male ( top 5 % sin score ) , single a4 = elite female ( top 5 % sin score ) , single b1 = male ( top 20 % sin score ) , married b2 = female ( top 20 % sin score ) , married b3 = male ( top 20 % sin score ) , single b4 = female ( top 20 % sin score ) , single c1 = male ( top 50 % sin score ) , single c2 = female ( top 50 % sin score ) , single c3 = male ( top 50 % sin score ) , married c4 = female ( top 50 % sin score ) , married d1 = bottom 50 % sin score d2 = bottom 40 % sin score d3 = bottom 25 % sin score d4 = single mother or bottom 15 % sin score the sin score was also adjusted to account for population size so that eighty percent of the population was in the c and d classes .