| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 1.69/5 | 3.03/5 |
| Vol 3-4 | 1.64/5 | 2.74/5 |
| Vol 5-6 | 1.73/5 | 3.00/5 |
| Vol 7-8 | 1.62/5 | 2.60/5 |
| Vol 9-10 | 1.65/5 | 2.70/5 |
| Vol 11-12 | 1.68/5 | 2.74/5 |
| Vol 13-14 | 1.88/5 | 3.42/5 |
| Vol 15-16 | 1.75/5 | 2.97/5 |
| Vol 17-18 | 1.70/5 | 3.09/5 |
| Vol 19-20 | 1.79/5 | 3.31/5 |
| Vol 21-22 | 1.89/5 | 3.53/5 |
| Vol 23-24 | 2.07/5 | 3.58/5 |
| Vol 25-26 | 2.14/5 | 3.70/5 |
| Overall | 1.79/5 | 3.70/5 |