Arguably, if it is just for sorting/delivery we could simply use the last two digits of the "length" portion of the address. That would enable any delivery service to sort the mail within the city block and still have a human readable equivalent in case the barcode becomes unreadable.
I should let this lie as an explained joke is never funny, but I just can't.
USPS - Delivery Point:
(1) A single mailbox or other place to which mail is delivered. A street address does not necessarily represent a single delivery point because a street address such as one for an apartment building may have several delivery points. (2) A specific set of digits between 00 and 99 assigned to every address that is combined with the ZIP+4 code to provide a unique identifier for every delivery address. The DP is encoded within the POSTNET or Intelligent Mail barcode.
Interesting, the last/only time I had to write code to determine delivery points was very early in my career (IBM mainframe COBOL) when postnet barcodes were a new thing and it was always just the last two digits of the street address. I see in the current CASS technical guide that a record type H may have multiple delivery point. Learn something new every day. Thanks.
Edit. As an aside, I think current Microsoft word still calculates it that way when you "bookmark" and address and insert a barcode field. At least it doesn't seem to be sending a query out to the USPS.
