HD - Industries, Land Use, Labor 735,660
HC - Economic History and Conditions 379,208
HV - Social Pathology, Criminology 306,545
HQ - Family, Marriage, Women 262,470
HF - Commerce 243,680
HB - Economic Theory and Demography 224,126
HG - Finance 201,739
HN - Social History and Conditions 123,835
HE - Transportation and Communications 111,289
HT - Communities, Classes, Races 108,606
HM - Sociology 106,674
HX - Socialism, Communism, Anarchism 83,362
HJ - Public Finance 80,003
HA - Statistics 57,172
H - Social Science 42,124
HS - Societies 15,404
F - General American History 3
B - Philosophy 2
E - United States History 2
N - Visual Arts 2
NC - Drawing, Design, Illustration 1
PS - American Literature 1