PHOTO: EPATHE MOST extreme phase of South Korea’s stock-market turmoil may be over after a historic sell-off flushed out leveraged positions and regulatory curbs sent trading in some of the riskiest products plunging. An index of volatility in South Korean shares recently fell to a two-month low, from a record high in June. The authorities took a number of steps in response to the whipsaw trading, vowing further measures to curb demand for leveraged products. The stock slump and tighter regulations flushed out many retail investors, who had been lured in by the market’s rally. South Korean stocks look cheap by some measures after the sell-off – with the Kospi trading at a record-low 5.1 times its 12-month forward earnings – but that still is not enticing money managers to rush back in.