| 变量 | GTI | GTI | GTI | GTI | 
| (1) | (2) | (3) | (4) | |
| treat × post | -0.169*** (0.0460) | -0.172*** (0.0498) | -1.332*** (0.432) | -1.539*** (0.482) | 
| Sub × treat | 
 | 
 | -0.0130*** (0.00269) | -0.0143*** (0.00288) | 
| Sub × treat × post | 
 | 
 | 0.0835*** (0.0260) | 0.0967*** (0.0289) | 
| Sub × post | 
 | 
 | -0.115*** (0.0257) | -0.116*** (0.0287) | 
| Sub | 
 | 
 | 0.104*** (0.0108) | 0.0758*** (0.0119) | 
| Growth | 
 | 0.0800* (0.0434) | 
 | 0.0703 (0.0441) | 
| Lev | 
 | 0.00276 (0.0753) | 
 | 0.0640 (0.0766) | 
| Ros | 
 | -0.343*** (0.106) | 
 | -0.230** (0.104) | 
| size | 
 | 0.123*** (0.0154) | 
 | 0.0712*** (0.0176) | 
| age | 
 | -0.0704*** (0.0174) | 
 | -0.0626*** (0.0170) | 
| TobinQ | 
 | 0.0397*** (0.0131) | 
 | 0.0284** (0.0127) | 
| 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 | 0.005 | 0.042 | 0.041 | 0.053 |