the quantity of names on a mailing list that meets the selection criteria for the target market. Each mailing list provides one or more attributes that can be used select a subset of the mailing list -- these are often called "selects." The mailer uses these selects to specify their target audience. For example, a mailing list that has state and gender as selects would enable you to select all females from New York, New Jersey, and Connecticut. The calculation of the count is typically performed by the mailing list owner's service bureau.