Privately provided public goods in a dynamic economy.

We show that when individuals can save (accumulate capital), they all eventually becomepublic-good contributors. In steady state, larger economies have more contributors. If thepublic good is normal, then its quantity increases in population size in the open-loopequilibrium, but not necessarily in the feedback equilibrium. If both private and public goodsare normal, then the open-loop equilibrium exhibits greater steady-state public provision thanthe feedback equilibrium. If private consumption is inferior the opposite is true. Interpretingindividuals as countries, our findings suggest that all countries over time will becomecontributors toward a global public good