Shiznit,
Over the last few months I have asked the same question. Of the current total members, how many cards have expired? This should be important to DPA. Your interest card only lasts one year. At a previous drive I was involved in we organized our cards by month. Prior to expiration we would mail a new self addressed, postage paid interest card to the expiring member.
Hiding FPL is a big issue with both Alpa members and DPA members. I believe hiding the true number of members by DPA is similar to hiding FPL data. Both organizations are not being forthcoming.