Marketing your book, which every author has to do, is a matter of constantly changing things to improve sales. The only way you can know what to change is to research and discover data that shows what's working and what isn't. One of the most significant data points is your book's sales. The current sales rank, along with the way customers are finding your book, can influence future sales in a surprising number of ways. To find information about this that you can really use, you'll need to research three different performance signals, three ways to measure the sales of your book.
The sales of your book might seem straightforward, but Amazon makes even this simple concept a bit tricky. Everything on the Amazon site is ranked according to its popularity. When searching for anything on their site, you'll be shown the most popular items first, on the theory that if it's most popular, it's the one that more people want. It's a bit of a self-fulfilling prophesy, because if an item is shown to more people, it will naturally sell to more people. In short, the book that sells the best is advertised to the most future readers looking for a book in the same genre.
Having a reader find your book and check out your cover and book description is the first goal in writing your book's listing. Once you get them on the page, your book will help to sell itself, but your listing does the majority of the work. The percentage of people who look at your book and actually buy it is known as the conversion rate. If you've got a lot of lookers and not a lot of buyers, your conversion rate is low. This is useful because it helps to narrow down where the appeal is breaking down, which helps you to pinpoint what needs fixing to increase your sales.
Click Through Rate
This is the most basic of data points, the number of people you've enticed to take a look at your book. How many searchers are actually clicking on your listing to check out your book description? If you can't get customers in the door, you'll never make a sale. Your click through rate is almost always a result of great keywords in your listing, which causes the Amazon algorithm to rank your book higher in the search.
Why These Three Performance Signals?
In order to increase book sales, you constantly need to change your listings every time they begin to fail. Watching these three performance signals will tell you where you need to make a change. If your click through rate is down, look to your keywords. To improve your conversion rate, your description and book cover need to be spot-on. And if your sales are down compared to other books in your niche, study what they're doing to keep their books best sellers and on the top 100 list, to find techniques you can use as your own.
Keep the Faith and May the Force be with You!