x1	x2	comp.sales	percent.change
0	0	4148	-5.7
0	0	2827	5.5
0	0	1972	-0.6
0	0	537	-3.4
0	0	2774	-0.4
0	0	1089	9
0	0	2038	-5.8
0	0	2863	1.9
0	0	381	4.7
0	0	3210	-13.9
1	0	7355	4
1	0	1409	2.2
1	0	720	9.5
1	0	3542	10.7
1	0	164	5.7
1	0	3159	9.2
1	0	3162	4.5
1	0	1132	5
1	0	848	9.3
1	0	2277	14.7
0	1	2074	0.7
0	1	784	8.2
0	1	3306	1.3
0	1	4392	9
0	1	2035	0.4
0	1	307	-4
0	1	1240	-3.5
0	1	210	4.2
0	1	1603	7.5
0	1	1807	-2.8