The world’s 400 richest people lost almost $194 billion last week as world stock markets began the year with a shudder on poor economic data in China and falling oil prices.

Forty-seven billionaires lost $1 billion or more during the worst week for U.S. stocks since 2011, according to the Bloomberg Billionaires Index. The combined drop was almost seven times the $29 billion lost in the first five trading days of 2015. The 400 people on the index had a combined $3.7 trillion at the end of the week, compared with more than $4 trillion a year ago.

Amazon.com founder Jeff Bezos, the best-performing billionaire in 2015, lost the most, his fortune dropping $5.9 billion this week as shares of the world’s largest online retailer fell more than 10 percent. Bezos is the world’s fourth-richest person with $53.7 billion.

The world’s richest person, Bill Gates, fell $4.5 billion to $79.2 billion, while Spain’s Amancio Ortega, the second richest, dropped $3.4 billion to $69.5 billion.

Casinos in Nevada log $662M loss

LAS VEGAS >> Nevada casinos collected almost 3 percent more revenue in fiscal 2015 than a year earlier but logged an overall loss in income for a seventh straight year, according to recent state Gaming Control Board data.

The $24.6 billion that casinos statewide collected in gambling and nongambling revenues in the 12 months ending June 30 represented a net loss of almost $662 million.

But that was less than the $744 million loss reported in fiscal 2014, when casinos took in $24 billion.

Board analyst Michael Lawton called the overall trend upward, with revenues almost back to the $25 billion last seen in 2007 and 2008.