If possible, also calculate the attrition rate by donor source. For example, if you have event-acquired donors, direct-mail-acquired donors and online-acquired donors, they probably aren’t all attriting at the same pace.
Once you know where your biggest “leakage” is occurring, you can focus on strategies to plug some holes. Are you talking to the donors in a similar manner in which they were acquired? For example, if your online-acquired donors are failing to give again, is it because you’ve been mailing to them instead of e-mailing them? Did you use one message to acquire donors (say helping children with cancer) and then switch messages (for example, to funding medical equipment) once they gave?
Pamela Barden is an independent fundraising consultant focused on direct response. You can read more of her fundraising columns here.