Economists have long sought to predict how macroeconomic shocks will affect individual welfare. Macroeconomic data and forecasts are easily available when crises strike. But policy action requires not only understanding the magnitude of a macro shock, but also identifying which households or individuals are being hurt by (or benefit from) the crisis. A popular solution is to extrapolate the welfare impact of a shock from the historical response of income or consumption poverty to changes in output, by estimating an 'elasticity' of poverty to growth. Although this method provides an estimate...