PRESORT Menu Help The following statistics can help you decide which labels you want to print. When Smart Mailer calculates these statistics, it counts each copy of each address as a separate piece. Direct pieces: The number of pieces that can be sorted into a direct group. Each direct group must have 10 or more pieces with the same 5-digit zip code. City/SCF pieces: The number of pieces that can be sorted into a city or SCF group. Each group must have 50 or more pieces with the same 3-digit zip code prefix. Residual pieces: The number of pieces that have valid state abbreviations and zip codes, but do not meet the requirements for direct, city or SCF pieces. Residual pieces do not qualify for the lower postage rate, but do count toward the 500-piece PRESORT minimum. Pieces that qualify for the lower postage rate: The total number of direct and city/SCF pieces. Pieces that count toward the minimum: The total number of direct, city/SCF, and residual pieces. Pieces that are invalid for PRESORT: The number of pieces that have invalid state abbreviations or zip codes, or any other errors.