Introduction
When authors do market research for their book they often look at similar books to see how they are doing in the market. However, Amazon doesn’t post unit book sales figures. At most, they provide the overall ranking of a book. This blog provides a table that can be used to estimate the daily sales based on a book’s overall rank.
Data Source
Hugh Howey published a series of reports on author earnings based on data he received from an author with advanced coding skills who had created a software program that can crawl online bestseller lists and grab mountains of data. He graciously made all of the data available for download and used for any purpose except to profit. So as long as you don’t send me money, we should be good.
Daily Sales
I have stratified the rankings and presented to the average for each strata to fit everything in a simple table.
This table shows the daily unit sales of Kindle books based on stratified rank for February 22, 2014, and April 24, 2014.
Data Limitations
Please be aware of some of the limitations of the data used to compile this table which includes the following.
- The data were collected at a point in time; therefore, it may not reflect current sales.
- Data is only for Kindle e-book sales. Therefore, figures may have to be adjusted upward where the book is being sold on other platforms or printed.
- Ranking can raise or drop sharply in the stratums with unit sales in the low single digits. Therefore, when looking at books with a sales volume in the single digits keep in mind that a single sale would cause book ranked in the millions to jump significantly. Likewise, a book club with a dozen members could also cause a book to suddenly jump in rank.
Conclusions
The table should prove useful if you are looking to get some idea as to the unit sales of a book.
Tony Dingwell 