Mismatch point

IN THE three months following the collapse of Lehman Brothers, as the world economy crumbled and investors scrambled for shelter, the dollar rose by 5% against a basket of other widely used currencies. In the past three months it has jumped by 11%; over the past year, by 22%—its fastest ascent in decades. The dollar is not yet in uncharted waters: one euro was worth one dollar in the early 2000s, for example. Its rise will help exporters in less vibrant parts of the world, notably Europe. But moves of this magnitude usually catch someone out, and the likeliest candidates this time are in emerging markets.