South Korean futures companies saw their earnings plunge nearly 70 percent in the second quarter of fiscal 2013 from three months earlier, mainly due to a decrease in their brokerage commission income, the financial regulator said Thursday. The combined net income of seven local futures firms came to 1.9 billion won (US$1.8 million) in the July-September period, compared with 6.1 billion won three months earlier, according to the Financial Supervisory Service (FSS).