| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.71/5 | 4.54/5 |
| Vol 3-4 | 2.96/5 | 4.66/5 |
| Vol 5-6 | 2.99/5 | 4.62/5 |
| Vol 7-8 | 3.06/5 | 4.66/5 |
| Vol 9-10 | 2.95/5 | 4.57/5 |
| Vol 11-12 | 2.94/5 | 4.51/5 |
| Vol 13-14 | 2.93/5 | 4.51/5 |
| Vol 15-16 | 2.94/5 | 4.67/5 |
| Vol 17-18 | 3.01/5 | 4.61/5 |
| Vol 19-20 | 3.14/5 | 4.68/5 |
| Vol 21-22 | 3.18/5 | 4.66/5 |
| Vol 23-24 | 3.07/5 | 4.56/5 |
| Vol 25-26 | 3.12/5 | 4.72/5 |
| Overall | 2.97/5 | 4.72/5 |