Zgi is a recentered influence function on the quantile of interest of the distribution of disposable equivalised income. The group differences in the predictors are weighted by the coefficients of families’ characteristics in 2014 to determine the endowments effect, the so called explained component. In other words, this latter measures the expected change in 2014 income quantiles, if those families had mid-2000s predictor levels. By contrast, the second term estimates the portion of the evolution of income that is due to changes in the association between poverty and household characteristics applied to 2014 predictor levels; and it measures the income difference resulting from variations in the “returns” that family and work characteristics from one period to the other, differences which are mainly due to changes in the distribution of market income and in the structure of social transfers.