In the “Weak Progressivity” case, there is a low income threshold below which individual income is exempted from the calculation of national capacity.[1] This weak case is used to define “Medium Progressivity” cases, in which the “development threshold” is set at $7,500 (approximately $20/day). This level is just a bit above a global poverty line that reflects empirical observations, so it too should be taken as a low estimate of “medium” progressivity.