| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.45/5 | 4.19/5 |
| Vol 3-4 | 3.44/5 | 4.16/5 |
| Vol 5-6 | 3.39/5 | 4.27/5 |
| Vol 7-8 | 3.48/5 | 4.33/5 |
| Vol 9-10 | 3.46/5 | 4.16/5 |
| Vol 11-12 | 3.44/5 | 4.22/5 |
| Vol 13-14 | 3.46/5 | 4.19/5 |
| Vol 15-16 | 3.45/5 | 4.01/5 |
| Vol 17-18 | 3.44/5 | 4.03/5 |
| Vol 19-20 | 3.44/5 | 4.28/5 |
| Vol 21-22 | 3.39/5 | 4.04/5 |
| Vol 23-24 | 3.46/5 | 4.05/5 |
| Vol 25-26 | 3.52/5 | 4.12/5 |
| Vol 27-28 | 3.51/5 | 4.12/5 |
| Vol 29-30 | 3.49/5 | 4.18/5 |
| Vol 31-32 | 3.43/5 | 3.90/5 |
| Overall | 3.45/5 | 4.33/5 |