| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.40/5 | 4.48/5 |
| Vol 3-4 | 3.06/5 | 4.48/5 |
| Vol 5-6 | 3.31/5 | 4.52/5 |
| Vol 7-8 | 3.32/5 | 4.47/5 |
| Vol 9-10 | 3.43/5 | 4.51/5 |
| Vol 11-12 | 3.44/5 | 4.49/5 |
| Vol 13-14 | 3.45/5 | 4.51/5 |
| Vol 15-16 | 3.02/5 | 4.42/5 |
| Vol 17-18 | 3.60/5 | 4.52/5 |
| Vol 19-20 | 3.56/5 | 4.51/5 |
| Vol 21-22 | 3.52/5 | 4.58/5 |
| Vol 23-24 | 3.84/5 | 4.67/5 |
| Vol 25-26 | 3.73/5 | 4.58/5 |
| Vol 27 | 3.30/5 | 4.46/5 |
| Overall | 3.43/5 | 4.67/5 |