At least 400 US moguls have topped the o

-, UNITED STATES: At least 400 US moguls have topped the one-billion-USD level in net worth, Forbes magazine reports in its annual survey of the wealthiest people in the United States. The latest survey, released late 21 September, 2006 was the first time all members of the Forbes 400 were billionaires, the magazine said. The collective net worth of the wealthiest Americans increased by 120 billion USD over the past year, to 1.25 trillion USD. Microsoft founder Bill Gates (top L) kept the top spot for the 13th year in a row followed by investor Warren Buffet (top R). Others on the list are Oracle founder Larry Ellison (bottom L) at number four; SpaceShipOne founder Paul Allen, at number five; and Personal Computer mogul Michael Dell came in at ninth. AFP PHOTO/ Top L-R: NICHOLAS ROBERTS/Bottom L: DEAN TREML/C: ROBYN BECK/R: VLADIMIR KMET (Photo credit should read -/AFP via Getty Images)