Amazon went public 20 years ago today - here's how much its earliest investors have earned

On May 15, 1997, Amazon, then an online bookstore, went public.

The company's stock has seen a stunning 36% compounded annual gain since then.

Amazon closed at $961.35 on Friday, giving the company a market value of about $466.2 billion. That's 490 times its split-adjusted stock price close at $1.96 on day one.

Amazon has earned fortunes for its most disciplined shareholders and its founder, Jeff Bezos, who in March became the world's second-richest person, overtaking Berkshire Hathaway CEO Warren Buffett and retail tycoon Amancio Ortega.

As The Wall Street Journal reported when Amazon first filed for its initial public offering, the company was just three years old and had no clear path to profitability. It faced a growing list of competitors that included Simon & Schuster and Barnes & Noble, each of which was already selling books online.

Amazon has now turned a profit for eight straight quarters, thanks in large part to the strength of its cloud-computing business, Amazon Web Services. Its more popular retail segment is not as profitable but is often cited as the existential threat not only to other bookstores but to any company in the brick-and-mortar retail business.

Walmart, America's largest brick-and-mortar retailer, is worth $228.25 billion, less than half what Amazon is worth.