Boosting your sales with a second book

My first book was published last November and although Thai Lottery has sold very well, it had plateaued after about four months. Sales were regular but at nothing like the levels I'd seen shortly after launch.  My second book, Thai Kiss, came out in the last week of May and is already well ahead of the trend set by its predecessor.

I'd made sure that I had the contact details for everyone who had contacted me about Thai Lottery and so I had a ready made market into which I could sell the second book. The response I got was fantastic. Thai Kiss, they told me, was even better than Thai Lottery.

The thing I'd not bargained for was the impact a second book would have on sales of the first. I'd obviously tapped into a new readership, at times Thai Lottery actually  outsold Thai Kiss, even though the second book was doing better than the first in its opening weeks. In short the publication of a second book sent the first on a higher trajectory than it had ever had before, even in its opening weeks.

If you are an author I'd love to hear any theories you have on why this might happen.  Maybe a second book ensures a degree of credibility with readers or maybe it's just the weight of mentions on the net. Whatever the reason, there seems to be no doubt that a second book helps to create a  virtuous circle. Now excuse me, I have to get to work on the third book.....