I always love it when people share revenue data for their apps / games / books / works, and it's been four years since The Motivation Hacker came out, so here's another updated graph of ebook sales by platform including the second year. (See also Second Year Book Sales, First Year Book Sales, Aftermath: The Motivation Hacker)
I forgot about checking the numbers for year three, and now it's been just over four years, so I thought I'd take another look. Looks like sales have more or less held steady on Kindle and the other ebook platforms, but CreateSpace paperbacks have come out of nowhere, so year four was better than year three or even two. Cool! (CreateSpace paperbacks cost more than ebooks, $7.99 to $2.99, but I set it so that the royalty is the same either way, about $2.21.)
Ratings kept falling on Amazon, from 4.4 two years ago to now 4.1. Goodreads inched down from 3.85 to 3.81, with a combined total of 633 ratings. I wrote the book quickly (about 200 hours total) and have now made about $17K, or around $86/hr. Not a huge amount, but not bad for something that I initially thought only 50-100 people would read.