| Variable meaning | Variable name | Variable calculation method |
| Panel A: Explained variable |
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| Proportion of independent directors | Independence | Number of independent directors/board of directors |
| Panel B: Main explanatory variables |
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| Ownership concentration | Top1 | Shareholding ratio of the largest shareholder |
| Equity balance | Z10 | The shareholding ratio of the largest shareholder/the shareholding ratio of two to ten shareholders, and the logarithm of the ratio value |
| Panel C: Main control variables |
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| Company size | Size | Logarithm of total assets of the company |
| Asset liability ratio | Leverage | Total liabilities/total assets of the company |
| Company growth capability | Growth | The growth rate of the company’s operating revenue |
| Profit margin of company assets | Roa | Net profit/total assets |
| Size of the board of supervisors | Supsize | The number of the board of supervisors is taken as the logarithm |
| Two jobs at the same time | Duality | The dummy variable is 1 when the chairman of the board concurrently serves as the general manager, otherwise, it is 0 |
| Shareholding ratio of senior executives | Excuratio | Number of shares held by senior executives/total equity |
| Enterprise value | TobinQ | Market value/book value of the company |
| Company age | Firmage | Financial reporting year—the year of the company’s listing, and take the logarithm |
| Free cash flow ratio | Fcf | (earnings before interest and tax + depreciation and amortization— increase in working capital—capital expenditure)/total assets |
| CEO tenure | CEO_tenure | Take the logarithm of the CEO’s tenure |
| Stock Volatility | Retstd | Volatility of monthly stock returns over 12 months |
| Nature of property rights | State | If the controlling shareholder is state-owned, it is 1, otherwise, it is 0 |
| Does the company deal with it in that year | ST | The dummy variable is 1 when the company specially processes it in that year, otherwise, it is 0 |
| Industry fixed effect | Industry | Industry dummy variable |
| Year fixed effect | Year | Year dummy variable |