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| my_date | my_shares | stock_price | new_shares |
|---|---|---|---|
| 2021-01-01 | 100 | 11 | 100 |
| 2021-01-02 | 100 | 11 | 0 |
| 2021-01-03 | 100 | 11 | 0 |
| 2021-01-04 | 150 | 12 | 50 |
| 2021-01-05 | 175 | 13 | 25 |
| my_date | my_shares | stock_price | new_shares | grp | my_cost |
|---|---|---|---|---|---|
| 2021-01-01 | 100 | 11 | 100 | 1 | 1100 |
| 2021-01-02 | 100 | 11 | 0 | 1 | 1100 |
| 2021-01-03 | 100 | 11 | 0 | 1 | 1100 |
| 2021-01-04 | 150 | 12 | 50 | 1 | 600 |
| 2021-01-05 | 175 | 13 | 25 | 1 | 325 |