53 Negro men & woman at 30 pounds each 1590 pounds 
29 children 580 pounds 
2 East India Indians 30 pounds 
1 Woman Servant 10 pounds 
-Maryland Prerogative Court (Inventories)
1. Unlike Virginia, where the Unites States as a whole seems to trace its history of servitude—quite inaccurately—black servants were simply referred to as negroes, the assumption being that a negro was a lifetime servant. Note their high value, twice that of an Indian and thrice that of a white. Negroes were regarded as investments because they were more obedient, easier to locate if they fled, less violent by a wide margin [with white servant uprisings and mixed race revolts five times more likely and much more successful than negro risings], illiterate and less likely to file and win law suits, but most importantly, as quasi-human race, could be bred to produce truly free labor.
2. At 20 pounds apiece, negro children were twice as valuable as a white adult, as they owed their entire life in service, not just their prime years.
3. By this time, East Indians hired to work as wage servants in London, but instead sold as chattel in America, were beginning to win court cases. So, the lack of time owed in this case and the pair price leads this reader to think that this was an older married couple. See the inventory below at 5.
4. It is highly unusual to find a white servant listed without time owed being noted. The only reasonable explanation is that the assessor judged that this woman was unlikely to outlive her term of service.
5. Inventory of Elizabeth Duhadway late of Ann Arundel County, 1 June 1729, To one East India Indian named Aron Johnson having two years and a half to serve 7 pounds, 10 shillings