Which formula correctly expresses the return on investment (ROI) for additional education or training?

• A. ROI = increase in annual net income × years of expected benefit ÷ cost of education.
• B. ROI = (increase in annual net income × years of expected benefit − cost of education) / cost of education.
• C. ROI = cost of education ÷ increase in annual net income.
• D. ROI = annual net income after education ÷ cost of education.

Answer: (B)

The idea here is to measure what you gain from education relative to what you spend on it. You take the increase in annual net income that the training brings, multiply it by the number of years you expect to benefit from that higher pay to get the total gain over that period. Then you subtract the upfront cost of the education to get the net gain. Finally, you divide that net gain by the cost to express the return as a ratio (often shown as a percentage). This format captures both how big the ongoing financial benefits are and how much was invested, giving a true sense of efficiency.

The other forms don’t fit this goal: multiplying annual gain by years without subtracting cost overstates the return by ignoring the investment; placing cost in the numerator or reversing the ratio changes the meaning of the metric; using annual income after education without accounting for the cost or the time horizon ignores the total net benefit.