I found this question by Okiura pretty fun to think about, and ended up typing way too much to go into a comment, so here’s a full post.
The question: “One question. Do you think that Bakemonogatari is effectively the best seller since 2000 given the fact that, as pointed in the FAQ, the consuming behavior has evolved (the non included second weeks being more important in the early 00′)?”
A very interesting question, albeit one I can only speculate about. To restate the question, “Is it possible that any show airing since 2000 with a lower Oricon average than Bakemonogatari may have outsold it, but not been reported as such due to poor Oricon coverage in the past?”
One source I’ll be using is the distributor reports referenced here: http://www.someanithing.com/167, but on the whole I’m doing a bunch of not-very-scientific guesstimation. Don’t take this too seriously, it’s just a thought experiment. I have to make big assumptions here and some could be totally inaccurate. I’m taking re-releases into account here by the way, because I think they’re relevant in this discussion.
• Distributor numbers imply Oricon accounted for roughly 80% of units shipped across Bake, Bake BD Box, and Nise. Those numbers came out only a few weeks after the final Nisemonogatari volume shipped, so it’s a reasonable assumption that coverage for the older Bake is less.
• 80% coverage would mean 98,500 shipped per volume, while 70% coverage would be around 112,500, and 60% coverage would be 131,000 but I think that’s getting a bit out there for a 2009 series in the BD era, so we’ll use the 70-80% range.
• BD box sold 31,831 per Oricon, the second most ever. Apply the 80% coverage modifier and that’s about 40,000, 70% is 45,500.
• Total theoretical average: 98,500-112,500 singles, 138,500-158,000 with BD box.
Let’s look at a few of the other possibilities.
Suzumiya Haruhi no Yuuutsu (2006) [42,525]
• Aired three years before Bakemonogatari and on DVD only. Its Oricon coverage number is much worse, in fact the worst I have on record, and I can believe that.
• Distributor claims put shipments (actually says sold, but let’s assume shipments to be conservative) at 800,000 for the original 8 discs (0 through 7) + the Gekisou concert. Gekisou was reported by Oricon at 28,584 so a generous guess would put that at 50,000 shipped, leaving 750,000 discs for the 8 DVD volumes. This would come to roughly 94,000 per volume.
• BD box is reported at 34,000, the most ever. Kadokawa says they shipped 50,000 units. There was also a second BD box that sold virtually nothing so I’ll not even bother adding that.
• Total theoretical average: 94,000 singles, 144,000 with BD box.
Likelihood it’s sold more? Singles look like they’re short even if you allocate Gekisou less of the 800k report. But when you factor in the monster BD box, it has a clear edge over Madoka and is right in the mid-upper theoretical Bake range.
Mahou Shoujo Madoka Magica [71,057]
• Aired two years after Bakemonogatari, so if anything reporting should have been better by that point, not worse.
• Distributor claims put shipments at 600,000 for the six TV volumes (71% Oricon coverage), which would come to 100,000 shipped per volume.
• BD box sold about 2.5x less than Bake, at 13,200. As a much more recent release I’m guessing coverage was better than 70%. Call it 80% and let’s say 16,500.
• Total theoretical average: 100,000 singles, 116,500 with BD box.
Likelihood it’s sold more? It’s possible if you only look at the singles, especially if it’s stayed in stock for long tail sales through the release of the movies. But when you factor in the BD box I think Bake’s advantage is too strong.
Code Geass: Hangyaku no Lelouch [45,366]
• Aired three years before Bakemonogatari and on DVD only initially. BDs came out a year later and are counted in the re-releases. Its Oricon coverage is quite a good bit lower than Bake’s.
• Distributor claims put shipments at 1,000,000 but that number includes: all S1 DVDs, s1 BDs v1-3, s2 DVD/BD v1-3, DVD magazine, and first Recap volume. Overall undercounting is 61%, and it’s very hard to tell how much of that comes from season one. But apply about 55% coverage and you get around 82,500 DVD singles.
• BD singles with 55% coverage would be 9,500.
• DVD box sold 4,580 per Oricon in 2012. If ~70% coverage, roughly 6,500.
• BD Box sold 13,520 per Oricon in 2013. If ~80% coverage (because it’s so recent) roughly 17,000.
• Total theoretical average: 98,500 singles, 115,500 with BD box.
Likelihood it’s sold more? It may be right around Madoka territory thanks to the three different re-releases but it’s probably well short of Bake and Haruhi.
Of all the series with very high Oricon averages and meaningful distributor claims to compare to, the three above are the best shots we have, I think. The other top-tier series by average are both too recent (BD-era) and have no re-releases and thus have no real shot. For example, Nisemonogatari from 2012 (obviously didn’t outsell Bake, no re-release, maybe 75,000 with undercounting), Fate/Zero from 2011 (no distributor claims, no re-release), and Shingeki no Kyojin from 2013 (no distributor claims beyond 84% v1 coverage, no re-release). Macross Frontier could put up a fight, but we don’t have distributor claims beyond 65% coverage for v1. K-ON! was 68% covered for all s1, s2, and event discs. If s1 was 60%, that’d be 73,000 or about 88,000 with re-release. Still a clear notch below the big three. All that’s left over 40k initial average are sequels (Geass R2, Monogatari SS) which didn’t outsell their higher ranking predecessors.
But there’s one mammoth (two actually, but we can focus on the better-selling season) in the room with massive singles sales and very strong BD boxes that, unfortunately, lacks any distributor claims.
Kidou Senshi Gundam SEED Destiny [68,735]
• Aired fully five years before Bakemonogatari, the oldest series discussed here.
• We have no distributor claims (that I know of), so I can only guess what its singles did.
• DVD boxes averaged 10,392.
• BD boxes averaged 10,105.
• This brings the average to 89,232 without any undercounting considered.
Likelihood it’s sold more? Pretty good (I say with zero evidence). It’s got to be at best 70% coverage for those singles (~100,000) and possibly much less (50-60%?), then add the 20k re-releases and their undercounting and I can’t see the combined average being any less than about where Haruhi is, and 70% Bake is well in striking distance (even 60% Bake). But who knows! I don’t. There’s also the first season of SEED of course, but at 10k lower singles average (but ~5k higher box average) than Destiny I think it’s safe to say Destiny has the better shot.
So to answer the question in the title? Dunno! But if you take re-releases into consideration I think it’s fair to say Seed, Destiny, Bake, and Haruhi are the top four, in some order. If you go with first-run singles only, Madoka and Geass s2 join in the fun.