| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.55/5 | 4.55/5 |
| Vol 3-4 | 3.41/5 | 4.52/5 |
| Vol 5-6 | 4.04/5 | 4.62/5 |
| Vol 7-8 | 4.07/5 | 4.62/5 |
| Vol 9-10 | 4.08/5 | 4.64/5 |
| Vol 11-12 | 3.64/5 | 4.56/5 |
| Vol 13-14 | 3.71/5 | 4.56/5 |
| Vol 15-16 | 3.43/5 | 4.58/5 |
| Vol 17-18 | 4.04/5 | 4.63/5 |
| Vol 19-20 | 3.94/5 | 4.62/5 |
| Vol 21-22 | 3.64/5 | 4.59/5 |
| Vol 23-24 | 4.11/5 | 4.64/5 |
| Vol 25-26 | 3.85/5 | 4.60/5 |
| Vol 27-28 | 3.96/5 | 4.65/5 |
| Vol 29-30 | 4.16/5 | 4.65/5 |
| Vol 31-32 | 4.22/5 | 4.69/5 |
| Vol 33-34 | 4.11/5 | 4.67/5 |
| Vol 35-36 | 4.10/5 | 4.64/5 |
| Vol 37-38 | 4.09/5 | 4.64/5 |
| Vol 39-40 | 3.88/5 | 4.60/5 |
| Vol 41-42 | 4.10/5 | 4.63/5 |
| Overall | 3.94/5 | 4.69/5 |