If you haven’t heard of the book “50 Shades of Grey” then you will more than likely been living in a cockerel’s boot since March.  It spawned film rights, a classical album and a Channel 4 documentary on the literary aspects of the naughty tome so from a publishing context, hey, it’s doing alright. 

Underneath all of the complaining and potential heavy breathing of the near global female population is some lovely and damn near sexy equations in action.  

“In to the Red Room slowly stepped Viral Coefficient far from him to let anyone know the numbers….”

The viral coefficient (or viral expansion loop) is a very easy way of measuring the user uptake of a referral. So if you tell 10 friends and only one takes up the referral you gave then the viral coefficient would be 1. 

VC = referrals * uptake ratio

If you have a viral coefficent of 1 then it’s an improvement anything about 1.2/1.3 then you are onto a good thing. Once you include the viral coefficent over a timeframe then you get a pretty good idea of the incline of your user base or sales pattern.  

So for arguments sake you buy a copy of “That Book” and then tell ten friends, nine of them buy a copy and then tell ten of their friends. This is the network effect in full flow. Span that over 30 days and the numbers will speak for themselves. 

With 50 Shades I would suggest that number was at least 1.6 or 1.7 for a period of time once the PR machine had sparked into life. Everyone talked about the book so everyone was so desperate to check if it was what their friends claimed it to be. 

“I am going to have coffee with Christian Grey… and I hate coffee.”

This is the reason the viral coefficient worked so well, readers were buying the book because everyone else was talking about the the book. “That book” as it’s commonly referred to caused a storm on many levels but mainly due to two threads, the nature of the content and by some about how badly written it was.  By those two elements readers just had to get hold of the book either to see what the quality of writing was or been seen in public with a naughty book.

These elements made the book a publishers dream, the perfect storm of media attention, reader shock (“you have to read this because….”) and the resulting viral coefficient.  How long it will last well that remains to be seen.