New Delhi, April 23 -- A $10 million purse? Believe it. A Hermes handbag owned by the late fashion icon Jane Birkin sold for that eye-popping, record-setting sum last summer at Sotheby's in Paris.

Now, if you can afford a $10 million pocketbook, there's no doubt you have plenty of dough. And the world is awash in money.

"The rich are getting richer, faster than everyone else, and they are shaping the economy," Liam Bailey of Knight Frank, the global real estate consultancy and estate agency, told Barron's.

Knight Frank just published its 20th annual wealth report-and the number of superrich is ballooning, especially in the U.S.

Of 713,626 individuals around the globe with a net worth of more than $30 million, 35% live in the U.S. Knig...