Bill Gates is richest man in US - again

The annual Forbes 400 ranking of the richest Americas is out, and for the 23rd consecutive year Bill Gates has maintained his status as the world's richest man, with a net worth of $81 billion.

Amazon founder Jeff Bezos leapfrogged Berkshire Hathaway chair Warren Buffett with a $67 billion net worth. Buffett had been in second place 15 years, but dropped to third place this year with a net worth of $65 billion.

Rounding out the top five are Facebook founder Mark Zuckerberg with $55.5 billion and Oracle founder Larry Ellison with $49.3 billion.