| Control | No | No | Yes | Yes | 
| 省份固定效应 | Yes | No | Yes | No | 
| 行业固定效应 | Yes | No | Yes | No | 
| 个体固定效应 | No | Yes | No | Yes | 
| N | 6392 | 6392 | 6391 | 6391 | 
| R2 | 0.3363 | 0.8376 | 0.5026 | 0.8712 |