How Reliabile are the Stats on Recurring Newsletters?
I've been looking at open stats on 5 specific dates of a weekly recurring newsletter and I'm wondering how reliable the reporting is (these were our most opened newsletters so far this year). In all instances, the number of opens I count for those dates now are significantly higher than the original count in May and January when these were originally sent. In one case, the increase was drastic (200%), which is so unusual that I'm finding it hard to believe that so many people opened the newsletter weeks or months later rather than there perhaps being some glitch or inconsistency with the reporting. I also see the same individuals opening those 5 newsletters, give or take 100 people or so. It's possible we have a core readership, but it just seems odd that there is very little variation in the readership. Have there been issues with this? How reliable are the stats on a recurring newsletter?