| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.92/5 | 4.62/5 |
| Vol 3-4 | 3.11/5 | 4.70/5 |
| Vol 5-6 | 3.06/5 | 4.69/5 |
| Vol 7-8 | 3.27/5 | 4.72/5 |
| Vol 9-10 | 2.62/5 | 4.57/5 |
| Vol 11-12 | 2.75/5 | 4.54/5 |
| Vol 13-14 | 2.66/5 | 4.58/5 |
| Vol 15-16 | 2.73/5 | 4.63/5 |
| Vol 17-18 | 2.58/5 | 4.64/5 |
| Vol 19-20 | 2.30/5 | 4.39/5 |
| Vol 21-22 | 2.62/5 | 4.61/5 |
| Vol 23-24 | 2.47/5 | 4.51/5 |
| Vol 25-26 | 2.32/5 | 4.42/5 |
| Vol 27-28 | 2.48/5 | 4.57/5 |
| Vol 29-30 | 2.53/5 | 4.56/5 |
| Vol 31-32 | 2.22/5 | 4.52/5 |
| Vol 33-34 | 2.15/5 | 4.30/5 |
| Vol 35-36 | 2.29/5 | 4.53/5 |
| Vol 37 | 2.90/5 | 4.61/5 |
| Overall | 2.64/5 | 4.72/5 |