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| sales_date | country | SUM(sales_volume) | fix_cost_per_day |
|---|---|---|---|
| 2020-12-01 | DE | 500 | 37.95066414 |
| 2020-12-01 | FR | 350 | 26.56546490 |
| 2020-12-01 | NL | 320 | null |
| 2020-12-02 | DE | 700 | 51.31964809 |
| 2020-12-02 | FR | 180 | 13.19648094 |
| 2020-12-02 | NL | 420 | null |
| 2020-12-03 | DE | 0 | null |
| 2020-12-03 | FR | 0 | null |
| 2020-12-03 | NL | 0 | null |
| 2020-12-31 | None | 0 | null |