Nigel French, an analyst at Taurus Investment Management, is analyzing Archway Technologies, a manufacturer of luxury electronic auto equipment, at the request of his supervisor, Lukas Wright. French is asked to evaluate Archway s profitability over the past five years relative to its two main competitors, which are located in different countries with significantly different tax structures.

. Which return metric should French use to assess Archways five-year historic performance relative to its competitors?