| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.42/5 | 4.31/5 |
| Vol 3-4 | 3.58/5 | 4.45/5 |
| Vol 5-6 | 3.57/5 | 4.49/5 |
| Vol 7-8 | 3.52/5 | 4.44/5 |
| Vol 9-10 | 3.45/5 | 4.39/5 |
| Vol 11-12 | 3.48/5 | 4.44/5 |
| Vol 13-14 | 3.62/5 | 4.53/5 |
| Vol 15-16 | 3.53/5 | 4.49/5 |
| Vol 17-18 | 3.59/5 | 4.47/5 |
| Vol 19-20 | 3.60/5 | 4.46/5 |
| Vol 21-22 | 3.57/5 | 4.45/5 |
| Vol 23-24 | 3.67/5 | 4.49/5 |
| Vol 25-26 | 3.48/5 | 4.38/5 |
| Vol 27-28 | 3.62/5 | 4.45/5 |
| Overall | 3.55/5 | 4.53/5 |