| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.28/5 | 4.69/5 |
| Vol 3-4 | 2.95/5 | 4.62/5 |
| Vol 5-6 | 3.12/5 | 4.64/5 |
| Vol 7-8 | 3.05/5 | 4.64/5 |
| Vol 9-10 | 3.36/5 | 4.68/5 |
| Vol 11-12 | 2.95/5 | 4.63/5 |
| Vol 13-14 | 2.76/5 | 4.54/5 |
| Vol 15-16 | 3.25/5 | 4.67/5 |
| Vol 17-18 | 3.15/5 | 4.63/5 |
| Vol 19-20 | 3.28/5 | 4.65/5 |
| Vol 21-22 | 3.31/5 | 4.64/5 |
| Vol 23-24 | 2.98/5 | 4.53/5 |
| Vol 25-26 | 3.29/5 | 4.64/5 |
| Vol 27-28 | 3.71/5 | 4.71/5 |
| Vol 29-30 | 3.27/5 | 4.69/5 |
| Vol 31 | 3.00/5 | 4.58/5 |
| Overall | 3.15/5 | 4.71/5 |