Stumbled across prior Sig Auctions. The last Sig earned 42x last night's auction:
Their auctions results have been discussed many times before of course (I think most recently here -
http://www.allposterforum.com/index.php/topic,12925.msg231622.html#msg231622), but the way it is laid out here really shows what remarkable growth they have gone in the last decade.
Their weekly auctions average price is about $100 per lot. It's amazing to do that kind of volume and maintain an average like that.
The signature auctions are even more impressive and show how Heritage's efforts to grow the market are really paying off. The earliest ones on your list did $700-800K and had 500-600 buyers, now Heritage's offerings regularly obtain 2.5-3x that dollar number and 2.5x the number of participants.
Is it any wonder that they are the undisputed leader in posters auctions? I think I've said before that if you add up the number of $100K individual poster sales from every auction house, not only has Heritage sold 85% of them, but that they've sold 25% of them in the last year or so.