| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.46/5 | 4.32/5 |
| Vol 3-4 | 2.81/5 | 4.62/5 |
| Vol 5-6 | 2.47/5 | 4.37/5 |
| Vol 7-8 | 2.61/5 | 4.41/5 |
| Vol 9-10 | 2.73/5 | 4.51/5 |
| Vol 11-12 | 2.69/5 | 4.45/5 |
| Vol 13-14 | 2.67/5 | 4.38/5 |
| Vol 15-16 | 2.55/5 | 4.30/5 |
| Vol 17-18 | 2.83/5 | 4.54/5 |
| Vol 19-20 | 2.63/5 | 4.43/5 |
| Vol 21-22 | 3.00/5 | 4.62/5 |
| Vol 23-24 | 2.69/5 | 4.37/5 |
| Vol 25-26 | 2.71/5 | 4.50/5 |
| Vol 27-28 | 2.73/5 | 4.37/5 |
| Vol 29-30 | 2.92/5 | 4.59/5 |
| Vol 31 | 2.56/5 | 4.31/5 |
| Overall | 2.70/5 | 4.62/5 |