| Variable | Variable defined |
| Sales | Sales revenue |
| Labor cost | Total employee compensation |
| ΔLn labor cost | the change in the natural logarithm of labor cost Δln labor cost = Ln(labor cost i, t) − Ln(labor cost i, t−1); |
| ΔLn sales | the change in the natural logarithm of sales revenue; Δln sales = Ln(sales i, t) − Ln(sales i, t−1); |
| LP | the value of 1 when year is more than 2008,and 0 otherwise. |
| Sec | the value of 1 when sales revenue decreases between periods t−2 and t−1, and 0 otherwise. |
| EI | in the natural logarithm of labor intensity; = Ln(100,000 × total number of employee/sales revenue); |
| Growth rate | Median operating income growth of all enterprises in the same industry; |
| Size | the natural logarithm of total assets at the end of the year t |
| Lev | total debt at the end of the year t/total assets at the end of the year t |
| Lshare | the equity ratio of the largest shareholder |
| Dual | the value of 0 when chairman and general manager are one person, and 1 otherwise |
| Ind | In accordance with the Commission in 2012 industry classification, the manufacturing industry to take the first two code, while the other industry to get the first code |