Series Read-through

Last month, I posted about reformatting my debut novel, Come Back. 

As part of the glow-up, I added a series link in the back matter, plus a QR code for the paperback, and a couple of sentences that told the reader which books contained stories of supporting characters (books 2 & 4). My goal was to improve series read-through.

The e-book interior was updated September 12th and the paperback September 16th, so, the backmatter changed roughly half way through the month. I compared both Kindle e-book sales and Kindle Unlimited page reads by looking at total sales and page reads for each of books 2-4 and calculating what percentage they each were of the sales/reads of book 1.

Ex: If I sold twenty copies of book 1 for the month and ten copies of book 2, read-through for book 2 would be 50%. 

Of course, I have no way of knowing whether the same reader bought all four books - or in the case of KU, whether customers were reading the entire series or even the entire book - but the numbers are still interesting to compare.

It's probably too soon to make much of the data, but here's what I've seen so far.

Page reads have remained fairly consistent, but look at e-book sales. Book 2 had been the least purchased book in the series. Not anymore.

It looks as if the mid-September glow-up achieved its objective.

Have you ever done anything to improve read-through of a series?

Did it work?