Optimal tax the optimum. Stipulating this condition results in the following formula for the optimal top tax rate, if incomes are Pareto distributed: formula_1 where: Empirical estimation of the parameters of this equation suggests that the revenue-maximising top tax rate is between approximately 50% and 80%, although this estimate neglects long-run behavioural responses, which would imply higher elasticities and a lower optimal tax rate. Saez's analysis can also be generalised to tax rates other than the top rate. In the late 1970s, Arthur Laffer developed the Laffer curve, which demonstrates that there are two effects of changing tax rates: an arithmetic effect—if
From each according to his ability, to each according to his needs Marx's terminology), the Soviet Union adapted the formula as: "From each according to his ability, to each according to his work (labour investment)". While liberation theology has sought to interpret the Christian call for justice in a way that is in harmony with this Marxist dictum, many have noted that Jesus' teaching in the "Parable of the Talents" (Matthew 25:14–30) affirms only "TO each according to his ability" (Matt. 25:15), and not "FROM each according to his ability". From each according to his ability, to each according to his needs "From each according to his ability, to each according to