| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-6 | 4.07/5 | 4.46/5 |
| Vol 7-12 | 4.03/5 | 4.45/5 |
| Vol 13-18 | 4.05/5 | 4.45/5 |
| Vol 19-24 | 4.03/5 | 4.45/5 |
| Vol 25-30 | 4.09/5 | 4.47/5 |
| Vol 31-36 | 4.07/5 | 4.47/5 |
| Vol 37-42 | 4.00/5 | 4.46/5 |
| Vol 43-48 | 4.06/5 | 4.47/5 |
| Vol 49-54 | 4.01/5 | 4.44/5 |
| Vol 55-60 | 4.03/5 | 4.46/5 |
| Vol 61-66 | 4.06/5 | 4.46/5 |
| Vol 67-72 | 4.03/5 | 4.46/5 |
| Vol 73-78 | 4.05/5 | 4.46/5 |
| Vol 79-84 | 4.07/5 | 4.47/5 |
| Vol 85-90 | 4.06/5 | 4.46/5 |
| Vol 91-96 | 4.06/5 | 4.46/5 |
| Vol 97-102 | 4.03/5 | 4.45/5 |
| Vol 103-108 | 4.05/5 | 4.45/5 |
| Vol 109-114 | 4.08/5 | 4.46/5 |
| Vol 115-120 | 4.11/5 | 4.49/5 |
| Vol 121-126 | 4.06/5 | 4.46/5 |
| Vol 127-132 | 4.06/5 | 4.49/5 |
| Vol 133-138 | 3.93/5 | 4.44/5 |
| Vol 139-144 | 3.96/5 | 4.43/5 |
| Vol 145-150 | 3.97/5 | 4.44/5 |
| Overall | 4.04/5 | 4.49/5 |