| In millions, except per share items | Sep-30-21 | Jun-30-21 | Mar-31-21 | Dec-31-20 | Sep-30-20 | Jun-30-20 | Mar-31-20 | Dec-31-19 |
| | 6-K | 6-K | 6-K | 6-K | 6-K | 6-K | 6-K | 6-K |
| Consolidated net income (loss) | | | | | | | | |
| Other comprehensive income (loss) | | | | | | | | |
| Actuarial gains and losses | | | | | | | | |
| Tax effect | | | | | | | | |
| Items not potentially reclassifiable to statement of income | | | | | | | | |
| Currency translation adjustment | | | | | | | | |
| Hedge reserve | | | | | | | | |
| |
| Items potentially reclassifiable to statement of income (loss), net of tax | | | | | | | | |
| Total other comprehensive income (loss), net amount | | | | | | | | |
| Comprehensive loss | | | | | | | | |