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| sales_date | country | SUM(sales_volume) | fix_cost_per_day |
|---|---|---|---|
| 2020-01-03 | DE | 500 | 0.0000 |
| 2020-01-03 | FR | 350 | 0.0000 |
| 2020-01-03 | NL | 320 | 0.0000 |
| 2020-01-30 | None | 0 | 64.5161 |
| 2020-02-15 | DE | 700 | 0.0000 |
| 2020-02-15 | FR | 180 | 0.0000 |
| 2020-02-15 | NL | 420 | 0.0000 |
| 2020-02-29 | None | 0 | 172.4138 |
| 2020-03-27 | DE | 180 | 0.0000 |
| 2020-03-27 | FR | 970 | 0.0000 |
| 2020-03-27 | NL | 670 | 0.0000 |
| 2020-03-31 | None | 0 | 129.0323 |