The point is that, to a typical person who doesn't know much about accounting or insurance, UnitedHealth's "profit margin" is understood to mean the fraction of

The point is that, to a typical person who doesn't know much about accounting or insurance, UnitedHealth's "profit margin" is understood to mean the fraction of the money I send them each month that's going into their pockets. Conventional accounting matches this intuition pretty well, and the source article's proposed alternative metric does not match it well at all.