The movement in retirements and resignation payments and other obligations:
| Increase (decrease) | Actuarial | |||||||||||||||||||||||
| Opening | current service | Benefits | (gains) | Currency | Closing | |||||||||||||||||||
| balance | provision | paid | losses | translation | balance | |||||||||||||||||||
| ThUS$ | ThUS$ | ThUS$ | ThUS$ | ThUS$ | ThUS$ | |||||||||||||||||||
| From January 1 to December 31, 2015 | 74,102 | (13,609 | ) | (3,824 | ) | 14,631 | (6,029 | ) | 65,271 | |||||||||||||||
| From January 1 to December 31, 2016 | 65,271 | 17,487 | (4,536 | ) | 3,105 | 995 | 82,322 | |||||||||||||||||
| From January 1 to December 31, 2017 | 82,322 | 21,635 | (5,399 | ) | (2,763 | ) | 5,292 | 101,087 | ||||||||||||||||