If you are serious about optimising your online presence as an author, K-Lytics is worth checking out. Their site asks the following rhetorical question:
Their paid market reports burrow into the details of hundreds of genres and micro-genres. Seeing the maths underneath the book markets is a bit disconcerting, but in a world governed by algorithms and visibility, these insights are essential. The specificity of some of the genres and sub-genres is almost comic: Scottish Romance (what about Scottish Time Travelling Romance?); Cosy Mystery; Urban Fantasy, etc.