HD - Industries, Land Use, Labor 3,898
HF - Commerce 2,695
HM - Sociology 2,151
H - Social Science 1,879
HB - Economic Theory and Demography 1,639
HC - Economic History and Conditions 1,553
HV - Social Pathology, Criminology 1,416
HQ - Family, Marriage, Women 1,245
HG - Finance 784
HN - Social History and Conditions 695
HT - Communities, Classes, Races 485
HJ - Public Finance 419
HX - Socialism, Communism, Anarchism 170
HE - Transportation and Communications 162
HA - Statistics 82
HS - Societies 10