Until this month, Harvard University Press had achieved two notable sales successes in the past 15 years. Stephen Jay Gould’s Dinosaurs in a Haystack: Reflections on Natural History and Charles Taylor’s A Secular Age both sold around 60,000 copies in each one’s first year, making them blockbusters by HUP’s scholarly standards.

By contrast, Thomas Piketty’s Capital in the Twenty-First Century has already sold around 80,000 copies in less than two months, and is currently sold out. According to Susan Donnelly, sales and marketing director at the 101-year-old house, that figure does not include an estimated 12,000 e-books sold (which Amazon is wisely peddling for a stratospheric $21.99), nor the 80,000 copies HUP is in the process of printing or the 35,000 it guesses it will print in the very near future. Do the math, and suddenly you are north of 200,000 books that the house expects to sell in a few months.

“It’s really been exciting,” said Donnelly. “People I haven’t talked to for years are calling me up: ‘You know I’m reading about your book!’”

And the majority of this success has happened in just the past 10 days, according to Donnelly, coinciding with a whirlwind tour Piketty conducted in the United States last week. “Between the past two days, we’ve sent 25,000 copies of the book into the world,” she said Wednesday afternoon. “People would buy more if we had ‘em.” As of Thursday morning, it remained the number-one bestseller on Amazon, where the hardcover is out of stock, and has reportedly entered the New York Times bestseller list. (Donnelly estimated that of the current English-language sales figures, 14,000 come from the United Kingdom and Europe.)

“We’ve definitely had high demand,” reported Lena Little, director of marketing at the Washington, D.C., independent bookstore Politics & Prose. “The one thing that was different” with this book, she added, is just how unexpected the sudden demand was. “It wasn’t like, ‘We don’t have it, but we can get in two days,’ like when there’s a good review in the Times or the Post,” she explained.