| 变量 | GTI | GTI | GTI | GTI | 
| (1) | (2) | (3) | (4) | |
| treat×post | -0.213*** (0.0391) | -0.216*** (0.0386) | -1.079** (0.477) | -1.039** (0.272) | 
| Sub×treat | 
 | 
 | -0.0143*** (0.00405) | -0.0150*** (0.00405) | 
| Sub×treat×post | 
 | 
 | 0.0677** (0.0297) | 0.0653** (0.0260) | 
| Sub×post | 
 | 
 | -0.0745** (0.0330) | -0.0686** (0.0280) | 
| Sub | 
 | 
 | 0.116*** (0.0130) | 0.0696*** (0.0119) | 
| Growth | 
 | -0.00463 (0.0317) | 
 | -0.00579 (0.0319) | 
| Lev | 
 | 0.0769 (0.0713) | 
 | 0.0980 (0.0718) | 
| Ros | 
 | -0.354*** (0.0852) | 
 | -0.325*** (0.0842) | 
| size | 
 | 0.160*** (0.0155) | 
 | 0.122*** (0.0169) | 
| age | 
 | -0.118*** (0.0173) | 
 | -0.111*** (0.0170) | 
| TobinQ | 
 | 0.0337*** (0.0110) | 
 | 0.0316*** (0.0110) | 
| 企业 | 控制 | 控制 | 控制 | 控制 | 
| 年度 | 控制 | 控制 | 控制 | 控制 | 
| 样本量 | 4400 | 4400 | 4400 | 4400 | 
| 调整R2 | 0.012 | 0.070 | 0.053 | 0.081 |