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
Date	Market Return	Company Return	Date	Market Return	Company Return	Date	Market Return	Company Return
7/12	.42	.63	2/8	.91	1.22	10/1	.62	.40
7/13	.00	.32	2/9	1.01	1.22	10/2	.52	.69
7/16	1.26	1.46	2/10	.52	.32	10/3	1.22	1.22
7/17	1.26	1.08	2/11	.72	3.34	10/6	.22	2.58
7/18	2.21	1.11	2/12	.42	.19	10/7	2.32	.45
7/19	.85	.70	2/15	1.22	2.78	10/8	.62	.62
7/20	.91	1.14	2/16	.62	.62	10/9	.42	.19
7/23	.73	.53	2/17	.42	.22	10/10	.42	.25
7/24	.22	.01	2/18	.42	.30	10/13	.00	.22

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 "0" wherever required. Do not round intermediate calculations and round your answers to 2 decimal places, e.g., 32.16.)

Days from announcement	Abnormal returns (Ri RM)				Average abnormal return	Cumulative abnormal return
	Delta	United	American	Sum
-4
-3
-2
-1
0
1
2
3
4