USPS Bulk Mail Sorter

For bulk mailings there are many standards required by the USPS in order to qualify for their bulk rates. One of the most tedious standards is pre-sorting every address according to Area Distribution Centers (ADC) which becomes even more tedious when working with "Flats" as defined by the post office. I work for a non-profit who used to manually sort through every address manually. So I designed a program for them that would speed up the process considerably. I'd like to continue to improve the program by receiving input and ideas.