| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.19/5 | 4.09/5 |
| Vol 3-4 | 3.09/5 | 4.02/5 |
| Vol 5-6 | 3.12/5 | 4.18/5 |
| Vol 7-8 | 3.13/5 | 4.17/5 |
| Vol 9-10 | 2.99/5 | 4.05/5 |
| Vol 11-12 | 3.11/5 | 4.12/5 |
| Vol 13-14 | 3.19/5 | 4.20/5 |
| Vol 15-16 | 3.13/5 | 4.08/5 |
| Vol 17-18 | 3.08/5 | 4.15/5 |
| Vol 19-20 | 3.01/5 | 4.15/5 |
| Vol 21-22 | 3.00/5 | 4.10/5 |
| Vol 23-24 | 3.06/5 | 4.05/5 |
| Vol 25-26 | 3.02/5 | 4.16/5 |
| Vol 27 | 3.37/5 | 4.28/5 |
| Overall | 3.09/5 | 4.12/5 |