Aside: I have met several people who admitted to downloading my books on torrents, and they gave me the $2 I would have made if they'd bought it :)
Still waiting for hunderds of US dollars worth of royalties :(
Standard book royalties for first-time authors in the U.S. are 15% for paperbacks and 20% for hardcovers. Established authors can make more than that.
>...royalties, at least among the top houses, are basically the same. Authors are paid, for hardcovers, 10% of the cover price on the first 5,000 copies sold, 12.5% on the next 5,000, and 15% thereafter. For paperbacks authors receive 7.5% of the cover price (occasionally with an escalator) and for eBooks 25% of the publisher’s net receipts. Many independent publishers pay lower royalties than these, but rarely do they pay higher. Competition between publishers takes the form of advance competition, with royalties generally being very similar, especially at the big houses.
https://literaryagentmarkgottlieb.com/blog/are-royalties-fai...
"Under standard royalties, an author gets roughly 20 to 30% of the publisher’s revenue for a hardcover, 15% for a trade paperback, and 25% for an eBook. So, very roughly, every hardcover release that earns out brings the author something like 25% of all revenue earned by the publisher. This percentage would drop once the paperback comes out, if it sells in significant numbers."
10% of cover price is usually the same as 20-30% of the publisher's revenue. You only drop down to 1.5% territory if your books are being discounted, meaning, if they aren't selling at cover price and they've been put into the bargain bin.
Computer books is a tiny fraction of the book market.