Compared to manga adaptations and original anime, which tend to be all over the map, I used to view light novel adaptations as more of a solved problem – popular light novels almost always become popular anime. However, in the past couple of years I’ve seen that rule broken several times, and it’s worth it to go back and examine the data, especially as the slant of adaptations in the year 2016 was not only unprecedented, but also looks to perhaps be the start of a trend.
I’m looking specifically at non-sequel, serial novels with anime adaptations that aired between 2010 and 2016. I took the raw list and disc sales data from someanithing on February 6, 2017, and excluded all sequels and non-serial novels from the list, since they can’t really be measured on the scale we’ll be looking at. The novel sales data comes from the charts posted on myanimelist and aggregated here.
Of the 120 series remaining in the sample, I was able to get some sort of novel sales data on 97 (-23 with no data). 89 had novels chart pre-anime, 91 had novels chart post-anime. The difference comes from the fact that the following 6 series ended concurrent with or before the anime adaptation’s airing:
Dantalian no Shoka
Maoyuu Maou Yuusha
To Aru Hikuushi e no Koiuta
Denpa Onna to Seishun Otoko
And the following 8 series only charted post-anime:
Mouretsu Pirates/Miniskirt Pirates
Hitsugi no Chaika
Inou-Battle wa Nichijou-kei no Naka de
Hai to Gensou no Grimgar
(Of these, only Grimgar’s post-anime volumes sold over 10,000 copies.)
Before we get started, the full sample of data can be found here. Now let’s get to some visuals!
1. What range of initial sales do LN anime come from? The answer has varied over the years.
As you can see, the amount of adaptations of popular series have declined over the years, sharply dipping in 2016. This is easily explained by the fact that most popular series have been already adapted by now. The field was ‘tapped’, so to speak.
-While the charts show a clear correlation between novels with initially high figures and successful anime, a handful of notable exceptions have accumulated over the years. Adaptations of >20k novel series with subpar disk sales and minimal novel boosts include:
Shinrei Tantei Yakumo
Seirei Tsukai no Blade Dance
Sakurako-san no Ashimoto ni wa Shitai ga Umatteiru
Densetsu no Yuusha no Densetsu
30k+ novels almost always seem to lead to hits (Yakumo excepted). The majority of exceptions here seem to come from that 20k-30k midrange.
On the other end, the novels with weaker pre-anime numbers that saw >4k disk sales and novel boosts include:
Amagi Brilliant Park
Jinrui wa Suitai Shimashita
Kono Subarashii Sekai ni Shukufuku wo
Mayoi Neko Overrun
I noted this more crudely on twitter weeks ago when I first started research.
-Series that ended congruent to their anime have a spotty record in disk sales that likely understates their true strength. Stuff that gets animated is going to see its source material in bookstores, and not just the secondhand kind.
Maoyuu is unique among the novels that ended pre-anime in that it had a particularly popular manga, and we can easily observe a boost in sales there.
It should be noted that the existance of spinoff manga is hardly unique to this series, but spinoff manga is quite possible to miss as a significant revenue source owing to the incompleteness of manga sales charts that only track the top 50 in a given week.
-Amagi Brilliant Park came out of the gate selling 20k per volume, but initial sales dipped off for the second and third volumes. The first-post anime volume showed ‘recovery’ to those initial levels, which I count as a boost.
-These figures are all considerably understating overall totals. For an example where I can cite figures, KonoSuba’s best oricon chart appearance pre-anime was about 13k for the 6th volume, but the sales total at that point was already up to 400,000. Though the anime caused that total to surge to 2,000,000 in the anime’s immediate aftermath, making it roughly proportional to the 12k->59k per volume increase, we can’t assume that proportionality will hold in all cases. These just happen to be the best set of consistent figures we have.
-Depending on the source you’re citing, the cost of making a 12 episode anime varies somewhat. Some sources say it’s 250 million yen for a 12-episode series, some say it’s 10 million yen per episode (which would be 120 million for a 12-pack).
With so much happening under the hood, it’s of limited use to play the “match budgets to gross revenues” game, but we’re doing it anyway. According to our sources, the minimum for a 12 episode anime is 120 million yen, and 250 is a reasonable figure. Numerous sources of revenue have to match that over the full lifetime of the series for an average anime to be viable to adapt.
If a novel volume costs about 700 yen, there are 10 volumes in an average series, and we take the median amount of a novel boost at 9000 copies, that means an average anime bump could make a series *a minimum* of 63 million yen if things peak out where they do on the charts (HA).
The median for disk averages is about 2400. At 30,000 yen per set, that works out to 72 million yen. Those two lowball figures combined get you to the minimum, and a not-unreasonable factor-of-2 increase for the long tails of each gets you to the more commonplace 250 mil. So the system works. Whew.
It’s super-reductive to take the time to argue that anime can make money in the abstract – over a hundred shows continue to come out year-by-year. The only interesting thing here is how big a part the sales of light novels can play in making that balance sheet function; you really only need a thousand or so high-rolling fans to latch onto it if your series makes an average-sized splash. And the two groups, the casual masses and high-rollers, both play surprisingly big and similar-sized roles in doing so. This would suggest that fans could do to respect one another.
-Does adaptation length matter? The two strongest-performing adaptations of 2016 were far and away KonoSuba and Re:Zero, and they share very similar profiles. Per-volume novel sales pre-anime were between 5 and 15k, then surged to 50k+. Both disk averages were a little bit over 10k. The only big difference was the massive gap in tone, and the fact that Re:Zero had 250% more screen time. Despite having twice as many episodes, Re:Zero didn’t make twice as much money – as we discuss above, the novels are significant, and the novel boosts were the same.
If KonoSuba and Re:Zero represent the apex performance of ultrashort versus 2-cour adaptations, Tenkyou no Alderamin and Occultic;Nine represent the nadir; 1 and 2-cour adaptations (respectively) that sold triple-digit disks and made no appreciable impact in the novel area. Let’s take these performances as the worst case. In Occultic;Nine’s case, you’re spending twice as much money for the same fart of a result. Not great. However, though that elementary logic that would seem to push lower-risk 1-cour projects, the actual landscape last year wasn’t that different for serial novel adaptations last year than it was in 2010. 2010 had 2 proper 2-cour adaptations (Densetsu no Yuusha no Densetsu, Durarara) plus one weird outlier (Katanagatari) out of 13 total, 2016 had 2. Same ol’. 2015 had 2 (Heavy Object and Gakuen Toshi Asterisk) out of a possible 20, 2014 had 2 (Mahouka Koukou no Rettousei and Hitsugi no Chaika) out of a total of 18. It’s difficult to split hairs over whether there “should” be fewer 2-cour adaptations, as they’re rare enough to begin with that practical statistics can’t effectively be brought into the argument.
Perhaps more relevant to ask is whether there will be more adaptations with 10 episodes and fewer with 13. KonoSuba provides a clear example that you don’t *need* the extra 3 episodes to attract casual attention and get your money’s worth on the novel sales front (as does the early onset of Re:Zero’s boost, actually). But hey, maybe it just takes more time to tell a good dramatic story than it does to land some jokes. While I personally think the shows that get 13 generally use that time, and the length may contribute to a better fan experience, minimizing risk is likely to become increasingly more relevant in a light novel market that is increasingly tapped out of guarantees.
In general, we seem to be moving towards “anything can get an anime” provided the cost is cheap. Counting ‘OVAs’ that air first in theaters like Yamato 2022 and Mahoutsukai no Yome, we’re up to 10 anime movies premiering in February alone. Zegapain got a movie (which was hella clever in recycling its footage for cheapness and getting away with a good product), and Makoto Uezu is on record saying that if that can get a movie, anything is possible. And hey, at the same event he said that, fans were requesting continuations to Astro Fighter Sunred, Kamisama Dolls, and even Kirikumas.