When will countries enact a universal basic income? A falsifiable Bayesian forecast for ten countries

A Monte Carlo decomposition of when ten countries enact a universal basic income, with every input stated as something that can turn out wrong. It puts a US UBI worth $6,000 a year at 4.0% by 2040 and 11.3% by 2050, and 39% that at least one of the ten enacts one by 2040. If the US unemployment trigger has not been met by 2040, the US figure falls to 0.2%. The first test comes soon: 58% that some government among the ten endorses a UBI by 2030. This page embeds the manuscript for model revision 2, dated 1 October 2026.