Table:
| FOR THE YEAR ENDED DECEMBER 31 | 2019 | 2018 |
| --- | --- | --- |
| Opening balance, January 1 | 707 | 636 |
| Incremental costs of obtaining a contract and contract fulfillment costs | 602 | 567 |
| Amortization included in operating costs | (523) | (477) |
| Impairment charges included in operating costs | (3) | (19) |
| Ending balance, December 31 | 783 | 707 |
Paragraphs:
Note 13 Contract costs
The table below provides a reconciliation of the contract costs balance.
Contract costs are amortized over a period ranging from 12 to 84 months.
Question:
What is the range of periods for contract cost amortization?
Answer: 12 to 84 months