The US dollar's resurgence has global investors pondering what it implies for capital flows into - and more likely out of - emerging markets next year. Ratings agency Fitch has analysed Asian economies, looking at which feels the biggest impact from a so-called "dollar shock", defined as a 10 per cent depreciation of local currencies against the greenback. For Taiwan and South Korea, a fall in their currencies against the dollar is good news, adding about 1 percentage point to gross domestic product growth. It is bad news for India and Thailand. Most intriguing in the analysis is what it implies for mainland China. The answer is almost nothing. So much for all the fretting about the yuan's on-off push towards six to the dollar.