There's nothing better for donor retention than donors that feel sincerely appreciated, and there's nothing more authentic than a hand-written thank you. While this might not be the most time-efficient method it is by far the most sincere. But, if you're crunched for time, sending an e-mail could also be an effective option. If you truly want to thank your donor like you mean it, consider Dennis Fischman's advice and:
For some it may come as a shock that being a data-driven organization might mean allowing members of your org to access more data.. and of all kinds: the good, the bad, and the in between. If you're one of the higher-ups in your nonprofit, the sooner you come to the realization that this (although scary) will empower your employees, the better. An article by Scot Chisolm, CEO of StayClassy, discusses the importance of this among two other Steps to Make Your Nonprofit More Data Driven.