Microsoft founder Bill Gates sits atop the prestigious Forbes 400 rich list of the wealthiest individuals in the United States for the 21st year in a row.
Like the rest of the rich in America, Gates is gaining wealth as stock market values of listed companies increases.
His personal net worth soared by $9 billion to $81 billion during the past year.
Many of the USA’s richest individuals kept their place on the list, but their combined wealth increased by an average 13% to a massive $2.9 trillion.
The average personal fortune of each person on the list is $5.7 billion.
Stock market gains boosts fortunes
Second behind Gates was renowned investor Warrant Buffett, with an estimated fortune of $67 billion, followed by Larry Ellison, founder of software giant Oracle on $50 billion.
Charles and David Koch, heads of petroleum conglomerate Koch Industries were fourth on the list with wealth of $42 billion each.
Facebook chief executive Mark Zuckerberg made the most money in the year, increasing his personal wealth from $15 billion in 2013 to $34 billion this year, mainly thanks to the company’s IPO on the New York Stock Exchange.
Zuckerberg is 11th in the list.
Facebook also increased the wealth of WhatsApp mobile messaging founder Jan Koum after going public with a proposal to buy his firm for $19 billion.
Koum was one of the 27 new billionaires to join the top 400, coming into snatch the 62nd place.
Men dominate rich list
Women took only 12% of the places on the list, giving them a combined net wealth of $273 billion.
Supermarket heiress Christy Walton is the richest woman not only in the United States but the world with a personal wealth of $38 billion derived from shares she inherited in the year, taking sixth place on the list.
She married into the family and gained her fortune when her husband John died in an air crash in 2005. Her wealth is increasing in line with the value of her shares in the corporation on a rising stock market.
Her sister-in-law Alice is the second wealthiest women, ranking ninth in the US with a fortune of $34.9 billion.
A new entrant to the top 400 is Elizabeth Holmes, 30, joining the list at 110th with a personal wealth of $4.5 billion.
Holmes made her money in just 10 years after co-founding biotech company Theranos, which invented new technology to analyse blood.