HD - Industries, Land Use, Labor 3,530
HF - Commerce 1,914
HG - Finance 823
HC - Economic History and Conditions 347
HB - Economic Theory and Demography 316
HT - Communities, Classes, Races 220
HJ - Public Finance 164
HM - Sociology 138
HQ - Family, Marriage, Women 138
HA - Statistics 101
H - Social Science 97
HV - Social Pathology, Criminology 91
HN - Social History and Conditions 62
HE - Transportation and Communications 45
HS - Societies 4
HX - Socialism, Communism, Anarchism 4