The Rates of Return on High School and University Educations

The rates of return on high school and university educations have

A) been estimated at 50 per cent per year.
B) been estimated at between 5 to 10 per cent per year.
C) not been estimated, but are assumed to be high.
D) been estimated as negative, but these are still good options for most.
E) been estimated to be essentially zero.