Good to hear for the authors and they deserve more pay, but somewhat to that end I will nitpick that the average cost of credits, or income that Amazon is getting for them, has increased a little over the last couple years in that they have reduced the discounting applied to the bigger yearly credit packs.

So someone on the 24 credit/year plan is paying closer to the monthly price per credit than they used to, meaning Amazon is receiving more money on average than they used to.