| Variable properties | Variable name | Variable abbreviation | Variable definitions |
| Dependent variable | Assets and liabilities | DAR | Total Liabilities/Total |
| Independent variables | Effective tax rate | ETR | Income tax expense/Pre-tax profit |
| Non-debt tax shield | NDTS | Depreciation/Total assets | |
| Control variables | Enterprise size | SIZE | Natural logarithm of total assets at the end of each year |
| Asset structure | AS | Total tangible assets/Total assets | |
| Profitability | ROA | Net profit/Total assets | |
| Growth | GROW | (End of current period of total assets − Beginning of current period of total assets)/Beginning of current period of total assets | |
| Cash flow | CASH | Net cash flow/Total assets from operating activities | |
| Current ratio | CA | Current assets/Current liabilities | |
| Bankruptcy risk | Z | Total assets/(3.3*Profit before interest and tax + Main business income + 1.4*Retained earnings + 1.2*Working capital) | |
| Industry | IND | Industry dummy variables |