The first regularity we observe when we try to measure income inequality in practice is that inequality with respect to capital is always greater than inequality with respect to labor. The distribution of capital ownership (and of income from capital) is always more concentrated than the distribution of income from labor. Two points need to be clarified at once. First, we find this regularity in all countries in all periods for which data are available, without exception, and the magnitude of the phenomenon is always quite striking.
