While weakness in South Korea's exports may get laid at the feet of the weak yen, the real cause is likely to be found further afield, Capital Economics said.
"Given the similarity of many of its exports to Japan's, Korea looks the most vulnerable" to the yen's latest bout of weakness following easing measures by the Bank of Japan," Gareth Leather, an economist at Capital Economics, said in a note Monday. "However, it is probably wrong to blame the poor recent performance of Korean exports on the weak yen."
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In October, South Korean exports rose 2.5 percent from a year earlier, bolstered by demand from the U.S. and China even as EU demand slackened, but some analysts viewed the extent of the improvement as a disappointment. The yen has lost around 10 percent of its value against the U.S. dollar since the beginning of September.
But correlation isn't causation, Leather notes.