Zero, zilch, nada: 0
This is how how many books I've sold in the past few days. I enrolled two of my books, Excuse me, where is the exit? and Candlelight Sinner, in the KPD select programme in hope to boost up the sales, particularly of my two novels and maybe the short stories, but the result is disappointing. I gave away about 5k in total (both books) and believe me I'm glad for it; it would hurt me even more had I given away 40k or more, like others. In the beginning it looked all fine; the short stories climbed rapidly to the top, as high as #3 of the humour charts and #7 (if I remember correctly) in the overall free charts, which was rather exciting to watch. When the three days were over, they didn't sell any for a few days, then sold about 100 more than usual (between 150-170 a month).
This is for my short stories only. The novels still sat on the shelves like blocks of concrete.
The second time was beginning of March to use up the remaining days for the short stories. The novels got a small boost, but still not worth a mention. That month, one year after publishing them, sales were at their lowest and then stopped completely. The KPD programme and free promotion has, in fact, killed my sales. Not really what I was expecting.
I was wary, but curious. Now I'm wiser. Though I have another day left for the novel, I will not use it. My fazit is that it's not worth it.
Of course it all can turn around again, once those, who downloaded Candlelight Sinner, read and like it, then proceed to buying Excuse me, where is the exit? and vice versa. Which may be a small percentage as people tend to download and stock up their Kindles faster than they can read, then delete most of the novels again without even reading them.
Although there are a few who are doing really well after the promotion, there are still more who, I guess, didn't benefit from it, or worse, as in my case, actually are counting dead bodies. I know that Talli Roland reported a decrease in sales, too. See her blog post here:
Have you experienced an increase or decrease in sales weeks after the promotion ended?