Small fluctuations from one year to the next may reflect issues with data and calculations rather than underlying economic realities. However, small changes that are sustained over time may indeed be significant. “ Because the Gini is a sluggish measure, even 1-2 Gini-point increases annually are a big deal,” Branko Milanovic, a World Bank expert on inequality, has written. One of the biggest problems lies simply in gathering basic income data.