| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 1.91/5 | 4.30/5 |
| Vol 3-4 | 1.78/5 | 4.08/5 |
| Vol 5-6 | 2.21/5 | 4.43/5 |
| Vol 7-8 | 3.44/5 | 4.61/5 |
| Vol 9-10 | 2.31/5 | 4.55/5 |
| Vol 11-12 | 2.34/5 | 4.48/5 |
| Vol 13-14 | 2.84/5 | 4.58/5 |
| Vol 15-16 | 2.96/5 | 4.58/5 |
| Vol 17-18 | 2.70/5 | 4.47/5 |
| Vol 19-20 | 2.86/5 | 4.56/5 |
| Vol 21-22 | 3.21/5 | 4.58/5 |
| Vol 23-24 | 4.16/5 | 4.72/5 |
| Vol 25-26 | 3.20/5 | 4.57/5 |
| Vol 27-28 | 3.68/5 | 4.62/5 |
| Vol 29-30 | 4.10/5 | 4.65/5 |
| Vol 31-32 | 4.10/5 | 4.66/5 |
| Vol 33-34 | 3.73/5 | 4.62/5 |
| Vol 35-36 | 4.14/5 | 4.67/5 |
| Vol 37 | 2.50/5 | 4.34/5 |
| Overall | 3.08/5 | 4.72/5 |