The impact of innovation on exports of Vietnamese manufacturing and processing enterprises: the moderating role of environmental uncertainty

Figures & data

Table 1. Summary of the variable scales used in this paper.

Variable

Measurement

Independent variables Innovation (Inno) Product innovation (ProdI) Process innovation (ProcI) Dependent variables Export propensity (EP) Export intensity (EI) Moderating variables Basic Infrastructure Constraints (EU1) Transport Infrastructure Constraints (EU2) Communication Infrastructure Constraints (EU3) Financing Constraints (EU4) Labor force Constraints (EU5) Skilled labor Constraints (EU6) Machinery/ equipment Constraints (EU7) Local Institution Environment Constraints (EU8) Control variables Size (SIZE) Human capital (HC) Capital Intensity (CAP) Non-state enterprises (Non-state) Enterprises FDI (FDI) Year Two-digit industry

Enterprises create innovation: “1” Yes “0” No Enterprises have product innovation: “1” Yes “0” No Enterprises have process innovation: “1” Yes “0” No Enterprises participate in exporting: “1” Yes “0” No The ratio revenue from export and totals of sales Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Having a value from 0 to 10 where: 0 = irrelevant, 1 = less important; 10 = very important Inverse of Provincial Competitiveness Index (PCI) Ln (number of employees) Ln (ratio of total salary to number of employees (million VND)) Ln (ratio of total capital to number of employees (million VND)) Enterprise is a non-state enterprise: “1” Yes “0” No Enterprise is an FDI enterprise: “1” Yes “0” No The variable is represented by 3 dummy variables, of which 2015 is used as the base of comparison. The variable represented by 24 dummy in the manufacturing industry is used as a reference.

Figure 1. Research model.

Table 2. Descriptive statistics.

Variable	Obs	Mean	Std. Dev	Min	Max
EP	17,932	0.46	0.50	0	1
EI	17,932	0.29	0.41	0	1
Inno	17,932	0.92	0.27	0	1
ProdI	17,932	0.81	0.40	0	1
ProcI	17,932	0.68	0.47	0	1
${\mathrm{\text{EU}}}_1$	17,932	4.89	3.73	0	10
${\mathrm{\text{EU}}}_2$	17,932	4.74	3.51	0	10
${\mathrm{\text{EU}}}_3$	17,932	4.36	3.39	0	10
${\mathrm{\text{EU}}}_4$	17,932	5.58	3.57	0	10
${\mathrm{\text{EU}}}_5$	17,932	5.31	3.34	0	10
${\mathrm{\text{EU}}}_6$	17,932	5.78	3.35	0	10
${\mathrm{\text{EU}}}_7$	17,932	5.92	3.49	0	10
${\mathrm{\text{EU}}}_8$	17,932	0.02	0.00	0.01	0.02

Table 3. The results of variance inflation (VIF).

Variables	VIF	1/VIF
Inno	1.99	0.50
ProdI	1.64	0.61
ProcI	1.29	0.78
${\mathrm{\text{EU}}}_1$	2.53	0.40
${\mathrm{\text{EU}}}_2$	3.23	0.31
${\mathrm{\text{EU}}}_3$	2.92	0.34
${\mathrm{\text{EU}}}_4$	1.95	0.51
${\mathrm{\text{EU}}}_5$	2.67	0.37
${\mathrm{\text{EU}}}_6$	3.18	0.31
${\mathrm{\text{EU}}}_7$	2.64	0.38
${\mathrm{\text{EU}}}_8$	1.00	1.00
Mean VIF	2.28

Table 4. The results of a Breusch-Pagan test.

	Export propensity				Export intensity
	HO: Constant variance Variables: fitted values of Export propensity				HO: Constant variance Variables: fitted values of Export intensity
Export	(1)	(2)	(3)	(4)	(1)	(2)	(3)	(4)
chi^2(1)	28.67	29.02	29.45	29.54	1003.02	1004.18	1003.57	1004.85
Prob > chi^2	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000

Table 5. Result of the impact from innovation to export propensity and intensity.

Variables	Dependent variables: Export propensity and Export intensity
	Export propensity				Export intensity
	(1)	(2)	(3)	(4)	(1)	(2)	(3)	(4)
Inno	0.601***	—	–	–	0.053***	–	–	–
	(0.124)				(0.014)
ProdI	–	0.304***	–	0.274***	–	0.027***	–	0.027***
		(0.089)		(0.090)		(0.010)		(0.010)
ProcI	–	–	0.265***	0.240***	–	–	0.010	0.009
			(0.076)	(0.076)			(0.009)	(0.009)
HC	0.405***	0.409***	0.404***	0.407***	0.040***	0.040***	0.040***	0.040***
	(0.069)	(0.069)	(0.069)	(0.069)	(0.007)	(0.007)	(0.007)	(0.007)
SIZE	1.483***	1.481***	1.481***	1.482***	0.161***	0.161***	0.161***	0.161***
	(0.070)	(0.069)	(0.068)	(0.069)	(0.007)	(0.007)	(0.007)	(0.007)
CAP	0.489***	0.487***	0.482***	0.487***	0.046***	0.046***	0.046***	0.046***
	(0.056)	(0.056)	(0.055)	(0.056)	(0.007)	(0.007)	(0.007)	(0.007)
Non-state	0.141	0.152	0.167	0.164	0.061	0.062	0.062	0.062
	(0.624)	(0.622)	(0.620)	(0.625)	(0.089)	(0.089)	(0.089)	(0.089)
FDI	5.455***	5.451***	5.438***	5.475***	0.752***	0.753***	0.752***	0.753***
	(0.641)	(0.639)	(0.636)	(0.641)	(0.092)	(0.092)	(0.092)	(0.092)
Year dummies (3)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Industry dummies (24)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Constant	−13.839***	−13.399***	– 13.534***	−13.678***	−1.573***	−1.551***	−1.532***	−1.555***
	(0.857)	(0.850)	(0.842)	(0.853)	(0.113)	(0.113)	(0.112)	(0.113)
Obs	17,898	17,898	17,898	17,898	17,920	17,920	17,920	17,920
Wald chi^2	2700.44	2683.82	2656.08	2661.06	4119.78	4114.76	4112.4	4115.03
Prob Wald	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table 6. The moderating role of environmental uncertainty in the linkage between Innovation and export.

	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
Variables	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
Inno	0.844***	0.894***	0.840***	0.761***	0.522***	0.602***	0.662***	6.156***	0.086***	0.094***	0.081***	0.067***	0.060***	0.072***	0.087***	1.140***
	(0.166)	(0.171)	(0.168)	(0.173)	(0.174)	(0.182)	(0.177)	(2.078)	(0.018)	(0.019)	(0.018)	(0.019)	(0.020)	(0.020)	(0.020)	(0.238)
${\mathrm{\text{EU}}}_1$	0.076**								0.006
	(0.031)								(0.004)
${\mathrm{\text{EU}}}_2$		0.087***								0.008**
		(0.031)								(0.004)
${\mathrm{\text{EU}}}_3$			0.084***								0.005
			(0.032)								(0.004)
${\mathrm{\text{EU}}}_4$				0.076**								0.004
				(0.031)								(0.004)
${\mathrm{\text{EU}}}_5$					0.010								0.003
					(0.031)								(0.004)
${\mathrm{\text{EU}}}_6$						0.043								0.006*
						(0.030)								(0.004)
${\mathrm{\text{EU}}}_7$							0.031								0.004
							(0.030)								(0.003)
${\mathrm{\text{EU}}}_8$								211.197								0.062***
								(138.263)								(0.016)
Inno* ${\mathrm{\text{EU}}}_1$	−0.076**								−0.009**
	(0.032)								(0.004)
Inno* ${\mathrm{\text{EU}}}_2$		−0.087***								−0.012***
		(0.032)								(0.004)
Inno* ${\mathrm{\text{EU}}}_3$			−0.077**								−0.008**
			(0.034)								(0.004)
Inno* ${\mathrm{\text{EU}}}_4$				−0.056*								−0.004
				(0.032)								(0.004)

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table

	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
Variables	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
Inno* ${\mathrm{\text{EU}}}_5$					0.013								−0.002
					(0.032)								(0.004)
Inno* ${\mathrm{\text{EU}}}_6$						−0.012								−0.006
						(0.032)								(0.004)
Inno* ${\mathrm{\text{EU}}}_7$							−0.021								−0.007**
							(0.031)								(0.004)
Inno* ${\mathrm{\text{EU}}}_8$								−346.012***								−0.068***
								(128.942)								(0.015)
HC	0.400***	0.401***	0.401***	0.401***	0.402***	0.401***	0.402***	0.404***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***
	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
SIZE	1.489***	1.489***	1.489***	1.491***	1.486***	1.488***	1.487***	1.484***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***
	(0.069)	(0.069)	(0.070)	(0.070)	(0.069)	(0.069)	(0.070)	(0.068)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
CAP	0.491***	0.490***	0.487***	0.486***	0.490***	0.489***	0.489***	0.491***	0.045***	0.045***	0.046***	0.046***	0.046***	0.046***	0.045***	0.046***
	(0.056)	(0.056)	(0.056)	(0.056)	(0.056)	(0.056)	(0.056)	(0.056)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
Non-state	0.130	0.129	0.126	0.131	0.148	0.149	0.133	0.127	0.059	0.066	0.068	0.062	0.061	0.061	0.062	0.060
	(0.625)	(0.626)	(0.625)	(0.628)	(0.627)	(0.627)	(0.625)	(0.621)	(0.089)	(0.090)	(0.090)	(0.089)	(0.089)	(0.089)	(0.089)	(0.089)
FDI	5.453***	5.447***	5.456***	5.502***	5.482***	5.501***	5.464***	5.428***	0.747***	0.754***	0.757***	0.751***	0.751***	0.751***	0.751***	0.751***
	(0.642)	(0.642)	(0.642)	(0.645)	(0.643)	(0.644)	(0.642)	(0.638)	(0.091)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)
Year dummies (3)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Industry dummies (24)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Constant	−14.085***	−14.123***	−14.075***	−14.114***	−13.893***	−14.025***	−13.963***	−17.123***	−1.588***	−1.598***	−1.595***	−1.584***	−1.581***	−1.594***	−1.588***	−2.578***
	(0.865)	(0.865)	(0.864)	(0.868)	(0.865)	(0.867)	(0.865)	(2.437)	(0.113)	(0.114)	(0.114)	(0.114)	(0.114)	(0.114)	(0.114)	(0.288)
Obs	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,920	17,920	17,920	17,920	17,920	17,920	17,920	17,920
Wald chi^2	2700.50	2697.72	698.71	2703.31	2692.40	2686.71	2695.78	2670.69	4132.11	4132.68	4125.90	4120.33	4119.52	4122.13	4128.61	4139.22
Prob Wald	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table 7. The moderating role of environmental uncertainty in the linkage between product innovation and export.

Variables	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
ProdI	0.632***	0.581***	0.550***	0.468***	0.367**	0.563***	0.594***	3.932***	0.037***	0.036***	0.034***	0.030***	0.030***	0.033***	0.036***	0.374**
	(0.134)	(0.134)	(0.133)	(0.143)	(0.143)	(0.154)	(0.150)	(1.453)	(0.010)	(0.010)	(0.010)	(0.010)	(0.010)	(0.010)	(0.010)	(0.151)
${\mathrm{\text{EU}}}_1$	0.075***								−0.001
	(0.021)								(0.001)
${\mathrm{\text{EU}}}_2$		0.067***								−0.002
		(0.022)								(0.001)
${\mathrm{\text{EU}}}_3$			0.068***								−0.001
			(0.023)								(0.001)
${\mathrm{\text{EU}}}_4$				0.061***								0.001
				(0.021)								(0.001)
${\mathrm{\text{EU}}}_5$					0.038*								0.001
					(0.022)								(0.001)
${\mathrm{\text{EU}}}_6$						0.078***								0.002*
						(0.021)								(0.001)
${\mathrm{\text{EU}}}_7$							0.062***								−0.001
							(0.021)								(0.001)
${\mathrm{\text{EU}}}_8$								75.582								0.016
								(101.089)								(0.011)
ProdI* ${\mathrm{\text{EU}}}_1$	−0.081***								−0.003**
	(0.023)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_2$		−0.071***								−0.003**
		(0.024)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_3$			−0.066***								−0.002
			(0.025)								(0.001)

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table

Variables	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
ProdI* ${\mathrm{\text{EU}}}_4$				−0.043*								−0.001
				(0.024)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_5$					−0.019								−0.002
					(0.024)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_6$						−0.057**								−0.003**
						(0.024)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_7$							−0.059***								−0.003**
							(0.023)								(0.001)
ProdI* ${\mathrm{\text{EU}}}_8$								−225.792**								−0.022**
								(90.169)								(0.009)
HC	0.406***	0.407***	0.407***	0.405***	0.405***	0.405***	0.407***	0.405***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***	0.040***
	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
SIZE	1.482***	1.483***	1.482***	1.483***	1.481***	1.487***	1.484***	1.483***	0.162***	0.161***	0.161***	0.161***	0.161***	0.161***	0.162***	0.161***
	(0.065)	(0.064)	(0.064)	(0.064)	(0.064)	(0.064)	(0.065)	(0.068)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
CAP	0.486***	0.486***	0.485***	0.483***	0.487***	0.486***	0.486***	0.490***	0.046***	0.046***	0.046***	0.046***	0.046***	0.046***	0.046***	0.046***
	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.056)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
Non-state	0.138	0.139	0.137	0.139	0.146	0.140	0.133	0.144	0.063	0.067	0.067	0.062	0.062	0.062	0.064	0.061
	(0.617)	(0.618)	(0.618)	(0.620)	(0.618)	(0.620)	(0.618)	(0.619)	(0.089)	(0.090)	(0.090)	(0.089)	(0.089)	(0.089)	(0.089)	(0.089)
FDI	5.354***	5.348***	5.346***	5.387***	5.354***	5.382***	5.356***	5.436***	0.752***	0.757***	0.757***	0.753***	0.753***	0.753***	0.753***	0.752***
	(0.633)	(0.634)	(0.634)	(0.636)	(0.634)	(0.636)	(0.634)	(0.636)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)	(0.092)
Year dummies (3)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Industry dummies (24)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Constant	−13.544***	−13.544***	−13.545***	−13.588***	−13.577***	−13.675***	−13.588***	−14.648***	−1.553***	−1.552***	−1.556***	−1.554***	−1.558***	−1.564***	−1.550***	−1.811***
	(0.840)	(0.840)	(0.840)	(0.842)	(0.840)	(0.843)	(0.841)	(1.893)	(0.113)	(0.113)	(0.113)	(0.113)	(0.113)	(0.113)	(0.113)	(0.218)
Obs	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,920	17,920	17,920	17,920	17,920	17,920	17,920	17,920
Wald chi^2	2597.79	2595.74	2594.76	2601.66	2588.93	2587.98	2595.07	2660.12	4121.29	4120.24	4116.95	4113.88	4114.56	4118.29	4119.31	4119.71
Prob Wald	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table 8. The moderating role of environmental uncertainty in the linkage between process innovation and export.

Variables	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
ProcI	0.290**	0.381***	0.379***	0.424***	0.116	0.018	0.193	1.862	0.023*	0.042***	0.035***	0.042***	0.029**	0.009	0.018	0.508***
	(0.117)	(0.118)	(0.116)	(0.129)	(0.129)	(0.138)	(0.135)	(1.214)	(0.013)	(0.013)	(0.013)	(0.014)	(0.015)	(0.015)	(0.015)	(0.128)
${\mathrm{\text{EU}}}_1$	0.015								−0.001
	(0.016)								(0.002)
${\mathrm{\text{EU}}}_2$		0.028*								0.002
		(0.016)								(0.002)
${\mathrm{\text{EU}}}_3$			0.035**								0.002
			(0.017)								(0.002)
${\mathrm{\text{EU}}}_4$				0.050***								0.004**
				(0.016)								(0.002)
${\mathrm{\text{EU}}}_5$					0.009								0.003*
					(0.017)								(0.002)
${\mathrm{\text{EU}}}_6$						0.012								0.002
						(0.017)								(0.002)
${\mathrm{\text{EU}}}_7$							0.011								−0.001
							(0.016)								(0.002)
${\mathrm{\text{EU}}}_8$								−31.697								0.022**
								(88.118)								(0.010)
ProcI* ${\mathrm{\text{EU}}}_1$	−0.007								−0.003
	(0.019)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_2$		−0.027								−0.007***
		(0.020)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_3$			−0.028								−0.006**
			(0.020)								(0.002)

*** p < 0.01.

** p < 0.05.

* p < 0.1.

Table

Variables	Dependent variables: Export propensity and Export intensity
	Export propensity								Export intensity
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
ProcI* ${\mathrm{\text{EU}}}_4$				−0.033*								−0.006***
				(0.019)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_5$					0.027								−0.004
					(0.020)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_6$						0.041**								0.000
						(0.021)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_7$							0.011								−0.001
							(0.020)								(0.002)
ProcI* ${\mathrm{\text{EU}}}_8$								−98.993								−0.031***
								(74.990)								(0.008)
HC	0.401***	0.400***	0.401***	0.397***	0.402***	0.404***	0.403***	0.401***	0.040***	0.040***	0.040***	0.040***	0.040***	0.039***	0.040***	0.040***
	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.069)	(0.068)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
SIZE	1.482***	1.483***	1.484***	1.490***	1.483***	1.484***	1.483***	1.470***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***	0.161***
	(0.068)	(0.068)	(0.068)	(0.068)	(0.067)	(0.067)	(0.068)	(0.063)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
CAP	0.484***	0.483***	0.482***	0.480***	0.484***	0.483***	0.482***	0.477***	0.046***	0.046***	0.046***	0.045***	0.045***	0.046***	0.046***	0.045***
	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.055)	(0.054)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
Non-state	0.168	0.160	0.159	0.154	0.174	0.190	0.164	0.146	0.061	0.069	0.072	0.064	0.063	0.062	0.063	0.058
	(0.620)	(0.621)	(0.621)	(0.624)	(0.622)	(0.624)	(0.621)	(0.611)	(0.089)	(0.090)	(0.090)	(0.089)	(0.089)	(0.089)	(0.089)	(0.089)
FDI	5.453***	5.448***	5.453***	5.504***	5.467***	5.509***	5.463***	5.285***	0.750***	0.758***	0.760***	0.754***	0.753***	0.753***	0.753***	0.749***
	(0.636)	(0.637)	(0.637)	(0.641)	(0.639)	(0.640)	(0.637)	(0.626)	(0.091)	(0.092)	(0.092)	(0.091)	(0.092)	(0.092)	(0.092)	(0.091)
Year dummies (3)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Industry dummies (24)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Constant	−13.471***	−13.519***	−13.542***	−13.672***	−13.466***	−13.499***	−13.474***	−12.634***	0.040***	0.040***	0.040***	0.040***	0.040***	0.039***	0.040***	0.040***
	(0.845)	(0.846)	(0.846)	(0.851)	(0.847)	(0.849)	(0.847)	(1.705)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)	(0.007)
Obs	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,898	17,920	17,920	17,920	17,920	17,920	17,920	17,920	17,920
Wald chi^2	2655.99	2658.26	2656.10	2663.78	2649.55	2640.81	2652.02	2553.02	4118.97	4123.52	4118.30	4120.15	4114.29	4114.74	4115.55	4127.19
Prob Wald	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000	0.000

*** p < 0.01.

** p < 0.05.

* p < 0.1.