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 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.