the rate of investment in countries with high and unpredictable rates of corruption is almost half of that in low -corruption countries. an analysis of more than a hundred countries over thirteen years found that when corruption increases by about two points on a ten-point scale, investment decreases by 4 percent , and gross domestic product falls by half a percent. corruption inflates the prices of goods by as much as a fifth, and severely curtails income growth for the poor. governments are not immune. corruption slashes governments legitimate revenues by as much as half, and adds from 3 to 10 percent to the cost of public services because citizens must bribe officials to acquire those services.