| (29) | Financial income and costs |
| | | 2017 | | 2016 | | 2015 | | |||
| Interest income | | $ | 848,148 | | | 637,977 | | | 482,442 | |
| Income from interest in accounts receivable | | | 8,961 | | | 8,357 | | | 7,492 | |
| Foreign exchange gain, net | | | 230,532 | | | 297,463 | | | 95,447 | |
| Effects of valuation of derivative financial instruments | | | - | | | 25,377 | | | 8,464 | |
| Financial income | | | 1,087,641 | | | 969,174 | | | 593,845 | |
| | | | | | | | | | | |
| Effects of valuation of derivative financial instruments | | | (84,094) | | | - | | | - | |
| Interest expense and financial expenses on financial debt | | | (188,597) | | | (129,769) | | | (93,964) | |
| Commissions and other financial expenses | | | (67,400) | | | (42,385) | | | (53,328) | |
| Financial costs | | | (340,091) | | | (172,154) | | | (147,292) | |
| Financial income, net | | $ | 747,550 | | | 797,020 | | | 446,553 | |