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Ross Compony; Westerfield, Incorporated; and Jordan Company announced a new agreement to market their respective products in China on July 18, February 12, and October 7, respectively. Given the information below, calculate the cumulative abnormal return (CAR) for these stocks as a group. Assume all companies have an expected return equal to the market return. Note: A negative value should be indicated by a minus sign. Leave no cells blank - be certain to enter "0" wherever required. Do not round intermediate calculations. Round your answers to 1 decimal place