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

$\backslash$table$[[$Delta$,$United,American$],[,$Market,Company,,Market,Company,,Market,Company$],[$Date$,$Return,Return,Date,Return,Return,Date,Return,Return$],[7/12,-\mathrm{.}50,-\mathrm{.}79,\frac{2}{8},-\mathrm{.}99,-1\mathrm{.}38,10/1,\mathrm{.}70,\mathrm{.}32],[7/13,\mathrm{.}00,\mathrm{.}40,\frac{2}{9},-1\mathrm{.}09,-1\mathrm{.}38,\frac{10}{2},\mathrm{.}60,\mathrm{.}85],[7/16,2\mathrm{.}48,2\mathrm{.}78,\frac{2}{10},\mathrm{.}60,\mathrm{.}30,\frac{10}{3},1\mathrm{.}30,1\mathrm{.}30],[7/17,-2\mathrm{.}48,-2\mathrm{.}14,\frac{2}{11},\mathrm{.}80,4\mathrm{.}93,10/6,\mathrm{.}30,-4\mathrm{.}17],[7/18,-2\mathrm{.}29,1\mathrm{.}19,\frac{2}{12},-\mathrm{.}50,-\mathrm{.}11,10/7,-2\mathrm{.}40,-\mathrm{.}30],[7/19,-\mathrm{.}93,-\mathrm{.}62,\frac{2}{15},1\mathrm{.}30,4\mathrm{.}10,10/8,\mathrm{.}70,\mathrm{.}70],[\frac{7}{20},-\mathrm{.}99,-1\mathrm{.}15,\frac{2}{16},\mathrm{.}70,\mathrm{.}70,\frac{10}{9},-\mathrm{.}50,-\mathrm{.}34],[\frac{7}{23},\mathrm{.}81,\mathrm{.}45,\frac{2}{17},-\mathrm{.}50,-\mathrm{.}26,\frac{10}{10},\mathrm{.}50,-\mathrm{.}30],[\frac{7}{24},\mathrm{.}30,\mathrm{.}01,2/18,\mathrm{.}50,\mathrm{.}22,10/13,\mathrm{.}00,-\mathrm{.}30]]$

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$.,32\mathrm{.}16.)$

$\backslash$table$[[\backslash$table$[[$Days from$],[$announcement$]],$Abnormal returns $(R_i-R_M),\backslash$table$[[$Average abnormal$],[$return$]],\backslash$table$[[$Cumulative$],[$abnormal return$]]],[$Delta$,$United,American,Sum$],[-4],[-3],[-2],[-1],[0],[1],[2],[3],[4,,,,,,]]$