Spatial inefficiencies in Africa’s trade network

I assess the efficiency of transport networks for every country in Africa. Using spatial data from various sources, I simulate trade flows over more than 70,000 links covering the entire continent. I maximise over the space of networks and find the optimal road system for every African state. My simulations predict that Africa would gain 1.3% of total welfare from reorganising its national road systems, and 0.8% from optimally expanding it by a tenth. I then construct a dataset of local network inefficiency and find that colonial infrastructure projects significantly skew trade networks towards a sub-optimal equilibrium today. I find suggestive evidence that regional favouritism played a role sustaining these imbalances. •I assess the efficiency of transport networks for every country in Africa.•Africa would gain 1.3% of total welfare from reorganising its national road systems, and 0.8% from optimally expanding it by a tenth.•Colonial infrastructure projects significantly skew trade networks towards a sub-optimal equilibrium today.•Regional favouritism might have a role sustaining these imbalances.