the first approach involves determining how much of the change in the poverty rate is due to income variation and how much to changes in income distribution the second approach weighs the different sources of household income focusing on labour market factors that affect labour income changes this breakdown reveals whether the change in income that pushed the poverty rate in a given direction is part of a general trend for all income groups or had a more specific effect on the poor the results of this analysis based on data from household surveys are presented in such a way that the effect of both components entirely explains the poverty rate variation in a given period see box