1. What is Membership Strength?

Research that Toastmasters International has done has indicated that, on average, around 20% of club members leave their clubs for various reasons over the course of a year. These can be factors out of your control (work, moves, etc.) and some factors in your control (meeting quality, club atmosphere, providing training).

To that end, there are two DCP goals about membership: gain four new members, then gain four more new members. If you assume charter strength (20 members), 20% comes out to four members, so meeting that first membership DCP goal is meant to keep you at charter strength, while the extra four is meant to foster growth.

While charter strength is a good baseline, your club should aspire to have around 30-35 members, with 80% or more of them in regular attendance. At around this point, you have more issues with scheduling enough speeches, and that's a good problem to have. You'll have all the people needed to run plenty of meetings, staff committees, and chair events.