Americans.

With an estimated worth of $570 million, Mrs. Marion MacMillan Pictet of Cargill Inc. is ranked number 62 on the list, while Mr. Ernest E. Stempel of the American International Group is ranked 78th, at $515 milliion.

Microsoft Corp. Chairman Mr. Bill Gates is back on top as the richest American, with a net worth of $9.35 billion from his burgeoning software empire, according to Forbes magazine.

Gates bumped stock tycoon Mr. Warren Buffett, with $9.2 billion, out of the number one spot, the biweekly business journal said its annual report.

As a group, the 400 richest are worth about $349 billion, nearly 21 percent more than the US defence budget.

There are a record 83 billionaires on the list, up from 79 last year. The minimum amount for entry rose to $310 million, from $300 million last year.

Mrs. MacMillan recently defeated Canadian millionaire and Bermuda resident Mr.

Michael DeGroote in a court battle over Perot's Island.