| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.05/5 | 4.43/5 |
| Vol 3-4 | 3.00/5 | 4.45/5 |
| Vol 5-6 | 3.04/5 | 4.48/5 |
| Vol 7-8 | 3.16/5 | 4.47/5 |
| Vol 9-10 | 3.17/5 | 4.49/5 |
| Vol 11-12 | 3.12/5 | 4.59/5 |
| Vol 13-14 | 3.31/5 | 4.51/5 |
| Vol 15-16 | 3.06/5 | 4.46/5 |
| Vol 17-18 | 3.23/5 | 4.54/5 |
| Vol 19-20 | 3.09/5 | 4.47/5 |
| Vol 21-22 | 3.08/5 | 4.51/5 |
| Vol 23-24 | 3.15/5 | 4.48/5 |
| Vol 25-26 | 3.45/5 | 4.59/5 |
| Vol 27-28 | 3.38/5 | 4.58/5 |
| Overall | 3.18/5 | 4.59/5 |