Table 1

Weighted sample characteristic by survey year

	2008	2010	2011	p Value^*
Price paid per cigarette (mean in Mex$)	1.24	1.36	1.64	<0.001
Cigarette expenditure (mean in Mex$)	6.90	7.60	8.37	<0.001
Purchase of discounted cigarettes
Yes	7.59	5.80	7.31	0.078
No	92.41	94.20	92.69	0.078
SID
Yes	17.24	25.14	21.48	<0.001
No	82.76	74.86	78.52	<0.001
No of cigarettes smoked per day
Five or less	55.39	52.63	53.33	0.909
More than five	44.61	47.37	46.67	0.909
Daily smoker
Yes	64.72	67.22	66.08	0.939
No	35.28	32.78	33.92	0.939
No of friends who smoke (mean)	3.22	3.17	3.00	0.148
Sex
Male	62.60	61.85	61.15	0.088
Female	37.40	38.15	38.85	0.088
Age, years (mean)	39.29	40.90	41.40	0.001
Income
Low	23.54	26.28	21.93	0.372
Medium	44.86	45.75	55.79
High	20.96	21.09	15.26
No information	10.64	6.88	7.03
Education
Low	27.19	31.21	29.46	0.030
Medium	56.09	53.4	55.57
High	16.72	15.39	14.97
City
Tijuana	14.32	15.98	15.93	0.645
Mexico City	22.56	23.32	23.47
Guadalajara	16.93	15.33	15.18
Monterrey	15.74	15.11	15.07
Puebla	15.40	15.16	11.18
Mérida	15.06	15.11	15.18