Income levels and income growth: some new cross-country evidence and some interpretative puzzles∗

The aim of this paper is to bring together two distinct ensembles of evidence concerning, at macro level, international distributions of incomes and their dynamics, and, at micro level, the size distributions of firms and the properties of their growth rates. We also include an intermediate level of observation, namely the properties of sectoral growth. First, our empirical analysis provides a fresh look at the international distributions of incomes and growth rates by investigating more closely at the relationship between the two entities and the statistical properties of the growth process. Second, we take a first step at identifying those statistical properties which are invariant with respect to the scale of observation (country, sector or firm) and those that are instead scale specific. This exercise puts forward a few major interpretative challenges.