Rentention Rate Calculation
Hi everyone, I did not see any existing posts about this, but if there is, please direct me to it. I need to calculate our donor retention rate comparing one year to the following year. In this case, 2013 vs. 2014. In the attached picture is a dummy record showing the donor made a membership donation in 2013, and then again 2014, so I would want a calculation that compared those two items and returned a 1, which I could then sum to get a count of all of the donors who gave both years. The portal is showing related income records from a different table. If they gave one year but not the next, it would return a 0 and thus they would not count as "retained."
For now I just want the retention % number, but later I hope to create a chart that shows this for different date ranges, or shows a floating retention rate from the same month of the previous year. In other words, I have larger aspirations which dictate any solution you might offer, so just throwing it out there.
Any help would be much appreciated.