Bezos surpassed Bill Gates after a surge in Amazon’s shares propelled the online retailer’s CEO’s net worth to $90.4 billion as of Thursday morning, according to Forbes. Gates held the top spot since May 2013, according to Bloomberg. It’s been a steady climb for the Amazon chief as he started the year as the fourth-richest person in the world. He’s since surpassed Inditex SA founder Amancio Ortega, now the world’s third richest, and Berkshire Hathaway’s Warren Buffett, now the world’s fourth richest person.

Fortune named Bezos its Businessperson of the Year in 2012 and its World’s Greatest Leader in 2016.

Amazon shares have risen 40% this year through Wednesday, and Bezos’s 17% ownership stake added $24.5 billion to his total net worth, Bloomberg reports. Amazon is also expected to see a quarterly revenue increase of about 22%, according to a Bloomberg analyst survey.

Amazon itself has had a big year, buying Whole Foods and expanding its Amazon Prime service into Singapore, presenting a challenge to Jack Ma’s Alibaba.