Actual Subscribers is tough to tease out. I usually do something like this:
– # of downloads at 6 weeks post release
– Average of the last 4 episodes of that number
– 80% of that average is your Subscriber #.
This kind of assumes that over 6 weeks everyone who’s up with ‘current’ episodes will have downloaded or listened to the episode. From there you can average over a few episodes (4 is a rough number, as you get more episodes you can take something like 10). This should filter out some of the noise of people who are new or are leaving. And from that you take a % of the total listens/downloads for a show and figure those folks are listening/downloading every episode and thus are Subscribed to the show.
iTunes and Stitcher don’t give you a subscriber # per se, so this is a good surrogate of it.
Cheers,
Craig
