Universities have boomed in recent decades. Higher-education institutions across the world now employ in the order of 15m researchers, up from 4m in 1980. These workers produce five times the number of papers each year. Governments have ramped up spending on the sector. The justification for this rapid expansion has, in part, followed sound economic principles. Universities are supposed to produce intellectual and scientific breakthroughs that can be employed by businesses, the government and regular folk. Such ideas are placed in the public domain, available to all. In theory, therefore, universities should be an excellent source of productivity growth.