Are paper billionaires real billionaires?
Shereen Marisol Meraji Aug 8, 2012
Facebook's falling stock price has knocked the company's founder, Mark Zuckerberg, off the top 10 tech billionaires list. But he's still worth a lot.
How healthy is a country's economy?
Ruchir Sharma Apr 26, 2012
Commentator Ruchir Sharma says just look at how its billionaires made their money.
