Amazon shareholders are having a good day.

The e-commerce juggernaut added more market value in one day than that of more than 400 individual companies in the S&P 500.

Amazon shares surged more than 13 percent to an all-time high midday Friday, a day after it reported better-than-expected earnings. The gain represented $61.9 billion of additional value for Amazon shareholders, who now own a company with a $529.1 billion total market value, according to FactSet.

The single-day increase is more than the market value of FedEx and approximately 420 companies in the S&P 500, according to FactSet. Amazon is also now the fourth-most-valuable company in the benchmark index.

FedEx’s current market value is about $61.8 billion.

Amazon CEO and founder Jeff Bezos is the richest man in the world, with $90 billion in wealth after Friday’s stock move.

The technology company is one of the best-performing large-cap stocks in the market. Its shares rallied 47 percent year to date through midday Friday versus the S&P 500’s 15 percent gain.