I wanted to be open about this process, so I'm giving the exact figures.
Sales of my first mystery, Haunting Refrain, had fallen steadily, going from 16 eBooks sold in June to 2 in October. In anticipation of Cold Comfort coming out in December, I did a little promotion for it and reduced the price to .99. It sold 5 at $2.99 and then 10 copies at .99, almost enough to buy a Big Mac. In January I put the price back to $2.99 and signed it up for Amazon's KDP Select program. I chose two days to offer free downloads, Jan 13 and 14. By the end of Jan 14, I had 4,779 downloads. I did this knowing I wouldn't make any money. It was for promotion and name recognition. It reached #3 on the free Kindle Mystery/women sleuths list, #5 on free Kindle romantic suspense, and #98 on the overall free Kindle list. I was thrilled.
As of this morning, HR has had 4,962 downloads with 7 units borrowed. Six units have been refunded. I'm not sure what the "refunded" means, but it may be units that were borrowed and returned. Also, most of those 183 units may be Amazon Prime borrows; Prime members can borrow one book a month for free. If so, any royalties for those units will be based on a percentage of the $700,000 pot Amazon provided, probably a very small amount. The month-to-date reports don't separate borrows from purchases. I'll have to wait for the regular monthly report to see that.
I hoped the Haunting Refrain promotion would help bring attention to Cold Comfort, which was released Dec 4. I don't have numbers for CC, but it went from 194,677 in ranking on Jan 11 to 30,176 on Jan 15, which must mean something. Even the print copy went up in ranking.
The Peeper, the suspense novel I co-wrote with
Jim Christopher, had a good jump in ranking (413,049 to 102,923), but I don't see those reports so I don't know what it meant in sales.
For me, this was much better than I hoped. I'm really pleased with it.