Ask HN: Authors, How much do you make from a single book annually?

I am currently in the early stages of non fiction book & just wanted to know what range of earnings to expect. I understand book earnings are skewed towards a very small minority of authors. So I expect the range to vary by alot. So if that means I will be an outlier, Also, I am also planning to self publish via Amazon[0] both digital & print. Any advice, tip are well appreciated. [0]: https://kdp.amazon.com/en_US/