HD - Industries, Land Use, Labor 736,706
HC - Economic History and Conditions 379,569
HV - Social Pathology, Criminology 306,978
HQ - Family, Marriage, Women 262,968
HF - Commerce 244,078
HB - Economic Theory and Demography 224,324
HG - Finance 200,866
HN - Social History and Conditions 124,004
HE - Transportation and Communications 111,389
HT - Communities, Classes, Races 108,786
HM - Sociology 106,892
HX - Socialism, Communism, Anarchism 83,463
HJ - Public Finance 80,063
HA - Statistics 57,196
H - Social Science 42,176
HS - Societies 15,418
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