Residential - The address is a residential address
Commercial - The address is a commercial address
[blank] - This happens when the address doesn't have enough information to ascertain RDI status, such as an R7 address.
R - root. This is the "preferred" location for the delivery point
S - shared. This is an address that shares a delivery point with the root address
[blank] - This address does not share a delivery point with any other address