| Group | Days in milking | Number of records |
| 1 | 5 - 35 | 8076 |
| 2 | 35 - 65 | 8608 |
| 3 | 65 - 95 | 8514 |
| 4 | 95 - 125 | 8912 |
| 5 | 125 - 155 | 8393 |
| 6 | 155 - 185 | 7713 |
| 7 | 185 - 215 | 6528 |
| 8 | 215 - 245 | 5409 |
| 9 | 245 - 275 | 4157 |
| 10 | 275 - 305 | 2635 |