In the past several weeks, Ohayocon-induced hiatus aside,* I’ve been compiling the sales data of light novels that became anime in 2011 and 2012. Put bluntly, the ecosystem of initial print sales->anime sales->additional print sales is very, very different from manga. With manga, it was very often the case that a comparatively unpopular manga like Blue Exorcist could produce the anime sales of a superhit while a way more popular manga like Sukitte Ii Nayo could produce anime sales all too close to nonexistent. Additionally, poor-selling anime like Kamisama Dolls and Zetsuen no Tempest often led to big surges in manga sales while popular anime like Yuruyuri produced negligible manga gains.
With light novels, that sort of thing can still happen, but it’s far rarer. In general, there are two dominant trends in the light novel market. One, better-selling light novels produce better-selling anime. Two, better-selling anime produce bigger increases in light novel sales. Though it should be noted, as always, that the extent to which this effect carries does vary somewhat.