| Contractual obligations |
The following table shows the breakdown of the third-party commitments and contractual obligations as of December 31, 2017 and 2016: 2017 | | Total | | | 2018 | | | 2019 and 2020 | | | 2021 and 2022 | | | Subsequent | | | | | | | | | | | | | | | | | | | Corporate debt | | | 643,083 | | | | 68,907 | | | | 253,393 | | | | 107,316 | | | | 213,467 | | Loans with credit institutions (project debt) | | | 4,628,289 | | | | 215,117 | | | | 457,853 | | | | 539,466 | | | | 3,415,853 | | Notes and bonds (project debt) | | | 846,919 | | | | 31,174 | | | | 53,620 | | | | 54,395 | | | | 707,730 | | Purchase commitments | | | 3,149,813 | | | | 141,867 | | | | 230,014 | | | | 259,845 | | | | 2,518,087 | | Accrued interest estimate during the useful life of loans | | | 3,129,321 | | | | 340,481 | | | | 630,108 | | | | 559,856 | | | | 1,598,876 | |
2016 | | Total | | | 2017 | | | 2018 and 2019 | | | 2020 and 2021 | | | Subsequent | | | | | | | | | | | | | | | | | | | Corporate debt | | | 668,201 | | | | 291,861 | | | | 376,340 | | | | - | | | | - | | Loans with credit institutions (project debt)* | | | 4,498,930 | | | | 183,929 | | | | 388,679 | | | | 459,361 | | | | 3,466,961 | | Notes and bonds (project debt) | | | 831,538 | | | | 27,225 | | | | 49,422 | | | | 48,740 | | | | 706,151 | | Purchase commitments | | | 2,894,146 | | | | 136,032 | | | | 263,398 | | | | 246,904 | | | | 2,247,812 | | Accrued interest estimate during the useful life of loans | | | 3,356,750 | | | | 332,408 | | | | 617,852 | | | | 543,927 | | | | 1,862,563 | |
| * | According to contracted maturities. |
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