	(1)	(2)	(3)	(4)
	est1	est2	est3	est4
VARIABLES	s_ijt	s_ijt	s_ijt	s_ijt
				
ldsps	-0.012***			
	(0.002)			
ltariff	-0.001*	-0.058***	-0.001*	-0.058***
	(0.001)	(0.017)	(0.001)	(0.017)
rta	0.003	0.040	0.003	0.044
	(0.003)	(0.035)	(0.003)	(0.036)
lsps		-0.054***		
		(0.012)		
dsps			-0.013***	-0.172***
			(0.002)	(0.034)
Constant	0.075***	-1.163***	0.077***	-1.165***
	(0.002)	(0.038)	(0.002)	(0.039)
				
Observations	72,859	76,219	75,607	76,219
R-squared	0.933		0.932	
Robust standard errors in parentheses				
*** p<0.01, ** p<0.05, * p<0.1				
