| Symbol | Definition | Value |
| dt | Demand in month t | Table 9 |
| D | Yearly demand from Section 4 | 100 PTFE |
| R | Monthly interest rate | 1.5% |
| PCt | Production capacity in month t | 12 PTFE |
| C | Cost to produce one PTFE | US$ 30,716.59 |
| IBt | Inventory in the beginning of month t | Table 9 |
| IEt | Inventory in the end of month t | Table 9 |
| IB1 | Inventory in the beginning of the first month | 5 PTFE |
| Imaxt | Maximum inventory in the end of month t | 6 PTFE |
| Imint | Minimum inventory in the end of month t | 1 PTFE |