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Table 4 Difference-in-differences regression estimates, sales outcome, Canada and US

	Parallel trend assumption testing	DD analysis
	(1)	(2)	(3)
GHW effect		− 0.038	− 0.057
		(0.037)	(0.045)
Canada dummy	0.177	0.156	0.089
	(0.240)	(0.132)	(0.154)
Canada specific time trend	0.001		0.001
	(0.001)		(0.001)
Cigarette price	0.003	− 0.148**	− 0.150**
	(0.118)	(0.058)	(0.059)
Unemployment rate	− 0.005	− 0.013	− 0.001
	(0.033)	(0.017)	(0.022)
Alcohol price	− 0.004	− 0.001	− 0.001
	(0.007)	(0.005)	(0.005)
R²	0.57	0.78	0.78
N	142	262	262

Analyses use deseasonalized monthly per capita sales data (in log) from Canada (treatment) and the US (control). The regression for pre-policy trend comparison uses 1995–2000 data. The difference-in-differences regression uses 1995–2005 data. Year fixed effects are included in regressions. Robust standard errors are reported
*p < 0.1; **p < 0.05; ***p < 0.01

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