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| id | date | variable | year |
|---|---|---|---|
| 1 | 2019-01-01 | blue | 2019 |
| 2 | 2019-01-15 | blue | 2019 |
| 3 | 2019-01-01 | red | 2019 |
| 4 | 2019-04-01 | blue | 2019 |
| 5 | 2019-06-01 | red | 2019 |
| 6 | 2020-01-01 | blue | 2020 |
| 7 | 2020-04-01 | red | 2020 |
| 8 | 2020-01-21 | blue | 2020 |
| 9 | 2020-06-01 | blue | 2020 |
| 10 | 2020-08-01 | red | 2020 |
| 11 | 2021-01-21 | blue | 2021 |
| 12 | 2021-02-21 | red | 2021 |
| date | variable | year | dr |
|---|---|---|---|
| 2019-01-01 | blue | 2019 | 1 |
| 2019-01-15 | blue | 2019 | 2 |
| 2019-01-01 | red | 2019 | 1 |
| 2019-04-01 | blue | 2019 | 3 |
| 2019-06-01 | red | 2019 | 2 |
| 2020-01-01 | blue | 2020 | 1 |
| 2020-04-01 | red | 2020 | 1 |
| 2020-01-21 | blue | 2020 | 2 |
| 2020-06-01 | blue | 2020 | 3 |
| 2020-08-01 | red | 2020 | 2 |
| 2021-01-21 | blue | 2021 | 1 |
| 2021-02-21 | red | 2021 | 1 |