Emerging-market stocks headed for the biggest weekly drop since September and currencies slid as the worsening commodities rout and slowing credit growth in China undermined the outlook for global economic expansion and trade. Equity gauges in China and Hong Kong led losses as the MSCI Emerging Markets Index pierced through the 50-day moving average for the first time since May. Energy companies paced declines among industry groups as Brent crude traded below $45 a barrel amid a bigger-than-expected U.S. glut. Russia’s ruble headed for its worst weekly drop in more than two months, while the currency of net-oil-importer Turkey advanced the most among peers. China stock-index futures slid after the country doubled margin requirements for stocks trading. Oil, China Credit Weigh on Markets Concerns are mounting that China’s faltering economy will deepen a rout in commodities as investors brace for the first U.S. interest-rate increase since 2006. China’s broadest […]