| Code | Definition | Number of Accessions |
| 1 | DIFFICULT TO REMOVE | 3 |
| 3 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 13 |
| 4 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 2 |
| 5 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 42 |
| 6 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 39 |
| 7 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 64 |
| 8 | (1 = DIFFICULT TO REMOVE, 9 = EASY TO PICK) | 2 |
| 9 | EASY TO PICK | 1 |