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| Company | Unit | Sep 2017 | Dec 2017 | Mar 2018 | Jun 2018 | Sep 2018 | Dec 2018 | Mar 2019 | Jun 2019 | Sep 2019 |
| Lexin FinTech | months | ... | ... | 11.5 | 12.8 | 13.6 | 14.2 | 12.5 | ||
| PPDAI Group | months | ... | ... | ... | ... | ... | ... | ... | ... |
Helgi Library 
