| 变量 | GTI | GTI | GTI | GTI | 
| (1) | (2) | (3) | (4) | |
| treat × post | -0.189*** (0.0335) | -0.182*** (0.0391) | -1.081*** (0.384) | -0.802* (0.416) | 
| Sub × treat | 
 | 
 | -0.0729*** (0.0270) | -0.0514* (0.0289) | 
| Sub × treat × post | 
 | 
 | 0.0637*** (0.0236) | 0.0536** (0.0258) | 
| Sub × post | 
 | 
 | -0.00988*** (0.00355) | -0.0163*** (0.00459) | 
| Sub | 
 | 
 | 0.0895*** (0.0160) | 0.0724*** (0.0170) | 
| Growth | 
 | 0.0135** (0.0556) | 
 | 0.124** (0.0558) | 
| Lev | 
 | 0.0347 (0.0740) | 
 | 0.0740 (0.0755) | 
| Ros | 
 | -0.211 (0.129) | 
 | -0.114 (0.129) | 
| size | 
 | 0.0578*** (0.0137) | 
 | 0.0199 (0.0158) | 
| age | 
 | -0.0583*** (0.0166) | 
 | -0.0527*** (0.0165) | 
| TobinQ | 
 | 0.0543*** (0.0156) | 
 | 0.0465*** (0.0159) | 
| 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 | 0.013 | 0.030 | 0.040 | 0.047 |