HD - Industries, Land Use, Labor 56,519
HV - Social Pathology, Criminology 28,767
HF - Commerce 27,538
HQ - Family, Marriage, Women 23,083
HC - Economic History and Conditions 18,480
HG - Finance 16,299
HM - Sociology 12,262
HB - Economic Theory and Demography 11,483
HN - Social History and Conditions 7,762
HT - Communities, Classes, Races 7,604
HE - Transportation and Communications 4,906
H - Social Science 4,066
HJ - Public Finance 3,764
HX - Socialism, Communism, Anarchism 2,983
HA - Statistics 1,165
HS - Societies 300