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| id | x | y | rollingavg |
|---|---|---|---|
| 1 | 1 | 1 | 25 |
| 1 | 1 | 2 | 25.0000000000000000 |
| 1 | 2 | 3 | 33.5000000000000000 |
| 1 | 2 | 4 | 55.0000000000000000 |
| 1 | 3 | 5 | 64.6666666666666667 |
| 2 | 1 | 1 | 78 |
| 2 | 1 | 2 | 78.0000000000000000 |
| 2 | 2 | 3 | 61.5000000000000000 |
SELECT 8