Delta, United, and American Airlines announced purchases of planes on July 18 (7/18), February 12 (2/12), and October 7 (10/7), respectively.

Delta United American MarketCompany MarketCompany MarketCompany Date Return Return Date Return Return Date Return Return 7/12 - 48 -.75 2/8 -.97 -1.34 10/1 .68 .34 7/13 .00 .38 2/9 -1.07 -1.34 10/2 58 .81 7/16 2.13 2.39 2/10 .58 .32 10/3 1.28 1.28 7/17 -2.13 -1.83 2/11 .78 4.53 10/6 28 -3.77 -2.27 1.17 2/12 - 48 -.13 10/7 -2.38 - 39 7/19 -.91 -64 2/15 1.28 3.71 10/8 .68 .68 7/20 -.97 -1.11 2/16 .68 .68 10/9 -48 -34 7/23 .79 47 2/17 -48 -28 10/10 48 - 32 7/24 .28 .02 2/18 .48 .24 10/13 .00 - 28 7/18 Given the above information, calculate the cumulative abnormal return (CAR) for these stocks as a group. All of the stocks have a beta of 1 and no other announcements are made. (A negative answer should be indicated by a minus sign. Leave no cells blank - be certain to enter "O" wherever required. Do not round intermediate calculations and round your answers to 2 decimal places, e.g., 32.16.) Abnormal returns (Ri - RM) Days from announcement Delta United American Sum Average abnormal return Cumulative abnormal return -4 -3 -2 -1 0 1 2 3 4