| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.23/5 | 4.55/5 |
| Vol 3-4 | 3.36/5 | 4.56/5 |
| Vol 5-6 | 2.90/5 | 4.42/5 |
| Vol 7-8 | 3.39/5 | 4.57/5 |
| Vol 9-10 | 3.40/5 | 4.52/5 |
| Vol 11-12 | 3.43/5 | 4.50/5 |
| Vol 13-14 | 3.36/5 | 4.54/5 |
| Vol 15-16 | 3.32/5 | 4.48/5 |
| Vol 17-18 | 3.66/5 | 4.55/5 |
| Vol 19-20 | 3.65/5 | 4.59/5 |
| Vol 21-22 | 3.37/5 | 4.55/5 |
| Vol 23-24 | 3.83/5 | 4.61/5 |
| Vol 25-26 | 3.52/5 | 4.47/5 |
| Vol 27-28 | 3.14/5 | 4.32/5 |
| Vol 29-30 | 3.21/5 | 4.48/5 |
| Vol 31-32 | 3.08/5 | 4.48/5 |
| Vol 33-34 | 3.17/5 | 4.41/5 |
| Vol 35-36 | 3.43/5 | 4.49/5 |
| Vol 37-38 | 3.63/5 | 4.61/5 |
| Vol 39-40 | 3.28/5 | 4.36/5 |
| Vol 41-42 | 3.38/5 | 4.50/5 |
| Vol 43 | 3.58/5 | 4.50/5 |
| Overall | 3.37/5 | 4.61/5 |