The overall aggregate ROI of college should be neutral, right? And therefore half the population will find their individual data points to be negative. If the

The overall aggregate ROI of college should be neutral, right? And therefore half the population will find their individual data points to be negative. If the ROI of college aggregated over all consumers is positive, then the colleges are mispricing themselves. As capitalists, they should charge more until they capture all the consumer surplus and the aggregate ROI for all consumers converges to zero. This is more or less what has happened over the past generation. (Not all colleges are strictly capitalist, of course, but in broad strokes this is what we've seen.)