As the power of the “Big Five” publishers (Hachette, HarperCollins, Macmillan, Penguin Random House, and Simon & Schuster) in the US ebook market wanes, self-publishing authors have overtaken them in terms of unit sales.
And though Author Earnings shows that in terms of gross dollars made off ebooks, Big Five publishers do better than self-published authors, the site also shows that as a group, self-published authors are taking home more of the pie than those who publish with the Big Five.
Source: Self-published authors have found a way to actually make money — Quartz