Steve Kihm, research director at Energy Center of Wisconsin, says you have to calculate ROI like this: Consider all years, the cash that went in and out, “and then calculate the ROI which is in our case 42 percent per year.” If you like big numbers the cumulative four year compound return on investment is 306%. But he likes to focus on the 42 percent per year number, which means that if the center hadn’t taken the money it spent on Mediasite equipment and hosting fees and had invested it in the bank, the bank would have had to pay the center 42 percent per year for each of the last four years...