A front-page Times article about authors and agents sidestepping traditional publishing houses and choosing instead to self-publish reports:
While self-published authors get no advance, they typically receive 70 percent of sales. A standard contract with a traditional house gives an author an advance, and only pays royalties — the standard is 25 percent of digital sales and 7 to 12 percent of the list price for bound books — after the advance is earned back in sales.
In my limited but direct experience, where it says "12" in that sentence the more accurate number would be "15."