| 变量 | GTI | GTI | GTI | GTI | 
| (1) | (2) | (3) | (4) | |
| treat × post | -0.204*** (0.0436) | -0.192*** (0.0464) | -0.723* (0.427) | -0.516** (0.440) | 
| Sub × treat | 
 | 
 | -0.0179*** (0.00519) | -0.0185*** (0.00557) | 
| Sub × treat × post | 
 | 
 | 0.0490* (0.0273) | 0.0391 (0.0283) | 
| Sub × post | 
 | 
 | -0.0367 (0.0308) | -0.0331 (0.0331) | 
| Sub | 
 | 
 | 0.0863*** (0.0192) | 0.0909*** (0.0218) | 
| Growth | 
 | 0.123** (0.0542) | 
 | 0.123** (0.0546) | 
| Lev | 
 | 0.0349 (0.0897) | 
 | 0.0284 (0.0906) | 
| Ros | 
 | -0.218* (0.119) | 
 | -0.238** (0.118) | 
| size | 
 | 0.0645*** (0.0174) | 
 | 0.00686 (0.0195) | 
| age | 
 | -0.0959*** (0.0196) | 
 | -0.0865*** (0.0196) | 
| TobinQ | 
 | 0.0574*** (0.0172) | 
 | 0.0536*** (0.0171) | 
| 企业 | 控制 | 控制 | 控制 | 控制 | 
| 年度 | 控制 | 控制 | 控制 | 控制 | 
| 样本量 | 2770 | 2770 | 2770 | 2770 | 
| 调整R2 | 0.013 | 0.031 | 0.046 | 0.055 |