Former Secretary of State Hillary Clinton‘s newly released book What Happened is on track to outsell President Donald Trump‘s business manifesto, The Art of the Deal.

On Wednesday, the Associated Press reported that What Happened sold more than 300,000 copies in combined formats since its launch–including 168,000 hardcover sales, the highest nonfiction opening release in the last five years.

What Happened is Clinton’s tell-all on the 2016 election, and it has already elicited numerous (sometimes heated) responses from fans, critics, and people mentioned in the book.

While precise figures for the number of copies of The Art of the Deal that were sold during its initial publication in 1987 are not readily available, some numbers can be extrapolated.

Timothy O’Brien, who wrote a biography of Trump, says The Art of the Deal only had a 150,000 copy run during its first printing, which would already place it behind What Happened.

To be clear: The Art of the Deal was a success–spending 48 weeks on the New York Times bestseller list, including 13 weeks as the number one selling book in the country. Since its release in 1987, Trump’s 11-step business book has sold more than 1 million copies, according to the New Yorker and Business Insider. CBS News reported in August of last year that, according to an unnamed source, The Art of the Deal sold 1.1 million copies, the highest number the Daily Dot could find regarding the total number of times the book has been purchased.

Tony Schwartz, the ghostwriter for The Art of the Deal and frequent Trump critic, told CBS News that 90 percent of the $1.6 million he made in royalties from the book came within the “first few years” after the book was published in 1987. That would mean Schwartz made $1.44 million over the first few years of the book’s release, or on average, $480,000 per year through the first three years.

Using the 1.1 million number, The Art of the Deal averages 36,667 sales per year over the past 30 years. If Schwartz’s estimate that 90 percent of sales came in the first few years, that equals out to around 330,000 copies sold, on average, between its release in November 1987 and November 1990—or roughly the same number of copies What Happened sold in its opening week.

Politifact, in attempting to verify Trump’s claim that The Art of the Deal was the “no. 1 selling business book of all time,” found Nielsen Bookscan data that showed the printed book–not digital copies–was sold 177,000 times since 2001, the earliest date for which the book-sales resource has data. As mentioned, just slightly over the 168,000 hardcover sales What Happened has garnered since its release last week.

While it’s difficult to say how quickly What Happened will reach 1.1 million copies sold, judging by its explosive first week, it should hit that milestone in far less than 30 years.