	(1)	(2)	(3)	(4)
VARIABLES	lnImput_VAT	lnOmput_VAT	lnImput_VAT	lnOmput_VAT
				
DID	-0.2582147***	-0.3197734***	-0.1024250*	-0.1649659***
	(-3.841)	(-4.336)	(-1.866)	(-2.676)
Size	0.4365843***	0.4173006***	0.4408288***	0.4364422***
	(6.746)	(6.878)	(5.677)	(5.890)
Lev	0.0597943	-0.0424624	0.0225281	-0.0304646
	(0.570)	(-0.414)	(0.193)	(-0.269)
FirmAge	0.0970313	0.1203253	0.2445414	0.4139433
	(0.305)	(0.327)	(1.112)	(1.580)
PR	0.0698650**	0.1141137***	0.1472385***	0.2187863***
	(2.502)	(3.169)	(3.902)	(5.183)
Employee	0.3831246***	0.3704778***	0.4096691***	0.3483179***
	(8.062)	(7.099)	(8.749)	(7.889)
FIXED	-0.3348188	-0.4831504	-0.5602027***	-0.2899840
	(-0.892)	(-1.238)	(-3.060)	(-1.404)
Constant	2.7666599**	3.1521228**	1.8224316	1.9279154
	(2.386)	(2.512)	(1.459)	(1.581)
				
Observations	4,338	4,338	5,025	5,025
R-squared	0.248	0.232	0.320	0.300
Number of firm_id	1,005	1,005	1,133	1,133
年份固定效应	YES	YES	YES	YES
个体固定效应	YES	YES	YES	YES
Robust t-statistics in parentheses				
*** p<0.01, ** p<0.05, * p<0.1				
