How To Calculate The Read-Through Rate Of Your Book Series

As a self-publisher, you are not only an artist but also a marketing professional. Your books do not sell themselves. So you have to invest in advertising.

Because advertising can be costly, many authors have moved away from writing single books to writing series.

The advantage is that many readers who buy Volume one of a series will also buy the other books of the same series. So instead of advertising many books, the author only has to promote Volume one of his series and sells the other books of the series as well.

The big question you have to ask yourself is: How many readers who bought book one will buy book two, book three, and so on?

Only when you know these numbers can you calculate how much advertising budget you have available to attract a new reader.

What data do you need?

If you have not yet tracked your book sales, you will have to do so first. For each book in the series, you need the sales figures for each month since its publication.

If you have a very long series and some of the books have been on sale for years, this is a significant effort. But if you collect the data for just one month every day, the task becomes manageable. It only takes longer to get all the data.

The calculation of the reading rate

The basis of the calculation is always the absolute sales figure of book one of the series. You refer to this number with each of the subsequent volumes.

Step One:

Divide the copies sold of Volume 2 by the copies sold of Volume 1.

Example from one of my series:

Volume 1: 18245 sales

Volume 2: 12508 Sales

12508:18245 = 0,6855

Read-through rate: 68.55%

Step two:

Repeat this calculation with all further Volumes.

You always divide the sales of the next volume by the sales of Volume one.

Now you have to average out all the different percentages you have received.

If you now object that the younger the calculated book is, the less significant the figures are, you are right. Of course, if the last book in the series was published only three months ago, it can't have generated nearly as many sales as Volume two from 2016, for example.

But this is compensated by the high significance of the figures of the older books in the series.

If you now add up all the percentages and divide the result by the number of your books, you get a conservative and quite a reliable average.

For illustration I show you the calculation for my series:

Volume 1 to Volume 2: 68%

Volume 1 to volume 3: 67%

Volume 1 to Volume 4: 72%

Volume 1 to Volume 5: 56%

Volume 1 to Volume 6: 63%.

Volume 1 to Volume 7: 49%.

Volume 1 to Volume 8: 85%

Volume 1 to Volume 9: 42%.

Volume 1 to Volume 10: 49%.

Volume 1 to Volume 11: 41%.

Volume 1 to Volume 12: 42%.

Volume 1 to Volume 13: 36%.

Volume 1 to Volume 14: 27%.

Volume 1 to Volume 15: 23%.

Volume 1 to Volume 16: 18%.

Average read-through rate: 53.73

What are you going to do with that number?

Let's say you sell your book, for example, for 2,99€ at Amazon.

Since you get 70% royalties, you make a profit of 1,92€ on a book.

For me, things look less rosy because I sell all the books in the series for 99 cents and only make 33 cents profit per book.

If I look at my above calculated read-through rate of 53.73%, it means, roughly speaking, that every second reader reads my whole series after buying one book.

My series is seventeen Volumes. So a reader who reads all the books brings me a profit of 17x33 Cent = 5,61€.

But since only every second reader (53,73%) reads my series, I have to halve the value, because I need two new customers to get the calculated 5,61€.

In my case, a new customer who buys Volume one is worth a total of 2.80€.

Now we finally get to what you can do with this number. This number is the basis for your advertising budget planning.

This number means that you make a profit if you spend less than 2,80 € on winning a new customer and a loss if you spend more.

Is that all you need to know?

No, of course, that is not all you need to know. Now that you know your read-through rate and thus the reader's value, you have a basis for deciding on your upcoming advertising campaigns.

What you don't know yet is how much the acquisition of a new reader on the respective advertising platform will actually cost.

That is what you have to find out now. First of all, you have no choice but to try out different platforms. Try Facebook ads, Amazon ads, and various paid newsletters.

Promote only books on each of these platforms that are not currently selling themselves, so that your data is meaningful.

Work on Facebook and Amazon with low daily budgets and long runtimes, so you don't burn too much money.

For paid newsletters, you have to decide whether you want to spend the fixed prices for a campaign. There you usually cannot influence the price.

Only one campaign must be running at a time. If you test Amazon Ads, you may not have Facebook Ads or a newsletter advertisement running simultaneously.

If you run these campaigns one after the other, you can calculate how much the acquisition of a new customer has cost you at the end of each campaign.

Only those campaigns where you have made a profit should be followed up.

With Facebook and Amazon Ads, you should not start without a plan. Both platforms are highly complex, and if you have no idea what you are doing, you can only make a loss there.

So learn everything about these two platforms before you invest money in them. Only through continuous testing will you find out what works and what doesn't. Only when you have found out what works can you say for sure how much a new customer you have won over one of these platforms costs.

Conclusion

As self-publishers, we are not only artists but also marketing experts, data analysts, statisticians, and researchers.

This article is not intended to intimidate anyone. I wanted to show that everyone can get reliable figures for their marketing decisions if they invest the necessary work.

There are no secrets and no abbreviations reserved for a few when it comes to book marketing. The platforms readily provide us with all the data we need to make good decisions.

If there is one thing you should keep in mind from this article, it would be this: Those who write series have much better chances to make money with their books than those who don't write series.

I hope that I could make it a little easier for you to get into this complicated subject with this article.

I would be happy to read in the comments about your experience in marketing your books.