🧪 Economics Development Economics Simulation

Standard growth theory assumes a country's capital stock converges to a single steady state, but development economics has long known this isn't always true: when the savings rate itself rises with income — because a household near subsistence has nothing left over to invest — the economy's accumulation equation can cross break-even three times, creating a low-level poverty trap, an unstable tipping point, and a high, prosperous equilibrium. This simulation renders that dynamic as a growing or shrinking 3D city, whose buildings track capital per worker in real time as it evolves under the classic dk/dt = s(k)f(k) − (n+δ)k equation with an S-shaped savings function. Adjust the subsistence threshold and credit-market access to relocate the tipping point, then fire a one-time "Big Push" aid injection to see whether it's enough to carry a trapped economy over the threshold into self-sustaining growth — the central policy question the Rosenstein-Rodan/Nelson/Azariadis–Drazen literature was built to answer.