Table 7.

Difference-in-differences Analysis of Large Soft Drink Tax Effects

Control Group	BMI			Overweight			Obese
	No tax changes	Matched on 1991 BMI	Census Division	No tax changes	Matched on 1991 BMI	Census Division	No tax changes	Matched on 1991 BMI	Census Division
Arkansas, entire period	−0.278*** (0.061)	−0.231*** (0.067)	0.152** (0.018)	−0.025*** (0.005)	−0.021*** (0.006)	0.039* (0.010)	−0.033*** (0.005)	−0.028*** (0.006)	−0.034** (0.007)
N	431,512	260,359	27,182	431,512	260,359	27,182	431,512	260,359	27,182
Ohio, entire period	0.065*** (0.022)	0.078* (0.038)	0.069 (0.042)	0.010*** (0.002)	0.011*** (0.003)	0.002 (0.003)	0.001 (0.002)	0.004 (0.002)	0.001 (0.004)
N	431,287	127,241	57,040	431,287	127,241	57,040	431,287	127,241	57,040
Ohio, enactment (1991–1994)	0.451*** (0.043)	0.644*** (0.062)	0.457* (0.197)	0.051*** (0.004)	0.058*** (0.008)	0.045*** (0.005)	−0.003 (0.004)	0.017*** (0.005)	0.000 (0.014)
N	271,964	81,614	35,984	271,964	81,614	35,984	271,964	81,614	35,984
Ohio, repeal (1993–1996)	−0.321*** (0.053)	−0.352** (0.114)	−0.391 (0.256)	−0.033*** (0.005)	−0.025** (0.009)	−0.048*** (0.009)	−0.004 (0.004)	−0.013 (0.011)	−0.009 (0.025)
N	301,382	88,185	39,410	301,382	88,185	39,410	301,382	88,185	39,410

Notes: each cell represents a separate regression, and the coefficients are the diff-in-diff coefficient comparing years in which a soft drink tax was in effect to years in which it was not, relative to the designated control group. Heteroskedasticity-robust standard errors that allow for clustering within states are in parentheses. Additional variables include male, age, black, Hispanic, high school grad, college grad, lagged state unemployment rate, state cigarette tax, indicators for state, year, and quarter, and state-specific time trends.

Source: BRFSS 1991 – 1996