In an article published in this journal in 2011, an alternative measure of inequality was suggested, which has subsequently become known as the Palma Ratio'. In this new article, the author of the original proposal revisits the argument for such a measure. Using new data, he examines whether the current remarkable homogeneity in the income share of the middle and upper-middle around the world the foundation of the so-called Palma Ratio' is an historically stable stylized fact, or whether it is a new phenomenon, the outcome of a process of convergence towards the current 50/50 Rule' (in which half of the population in each country located within deciles 5 to 9 tends to appropriate about 50 per cent of the national income, or just above). Although partly written in response to a comment on the 2011 paper (published in this issue), the article also makes a substantive further contribution to the literature on inequality and the statistics to measure it.