| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.09/5 | 4.35/5 |
| Vol 3-4 | 4.25/5 | 4.55/5 |
| Vol 7-8 | 4.09/5 | 4.55/5 |
| Vol 10-11 | 2.05/5 | 3.15/5 |
| Vol 12-13 | 4.12/5 | 4.55/5 |
| Vol 14-15 | 3.53/5 | 4.35/5 |
| Vol 16-18 | 4.25/5 | 4.55/5 |
| Vol 20-21 | 3.75/5 | 4.35/5 |
| Vol 23-24 | 2.87/5 | 4.45/5 |
| Vol 25-26 | 4.25/5 | 4.55/5 |
| Vol 27-28 | 4.02/5 | 4.55/5 |
| Vol 29-33 | 3.25/5 | 4.15/5 |
| Vol 34-35 | 3.25/5 | 3.55/5 |
| Overall | 3.50/5 | 4.55/5 |