HD - Industries, Land Use, Labor 734,795
HC - Economic History and Conditions 378,828
HV - Social Pathology, Criminology 305,981
HQ - Family, Marriage, Women 261,925
HF - Commerce 243,430
HB - Economic Theory and Demography 223,946
HG - Finance 201,608
HN - Social History and Conditions 123,657
HE - Transportation and Communications 111,175
HT - Communities, Classes, Races 108,411
HM - Sociology 106,462
HX - Socialism, Communism, Anarchism 83,286
HJ - Public Finance 79,962
HA - Statistics 57,043
H - Social Science 42,060
HS - Societies 15,388
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