FIGURE 1.7 The Rich Get Richer The Gini index is a measure of income equality, ranging from zero (everyone equal) to one (one person has all the money). Values here are after taxes, and they show that the gap between rich and poor is widening in the United States and Finland but less so in other countries. Worldwide, the gap between the richest people and the poorest is even wider, estimated at about 0.63 in the Gini.