| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.33/5 | 4.39/5 |
| Vol 3-4 | 3.06/5 | 4.23/5 |
| Vol 5-6 | 3.20/5 | 4.39/5 |
| Vol 7-8 | 3.27/5 | 4.40/5 |
| Vol 9-10 | 2.94/5 | 4.23/5 |
| Vol 11-12 | 3.36/5 | 4.37/5 |
| Vol 13-14 | 3.32/5 | 4.31/5 |
| Vol 15-16 | 3.34/5 | 4.34/5 |
| Vol 17-18 | 3.28/5 | 4.21/5 |
| Vol 19-20 | 3.48/5 | 4.43/5 |
| Vol 21-22 | 3.34/5 | 4.33/5 |
| Vol 23-24 | 3.31/5 | 4.32/5 |
| Vol 25-26 | 3.32/5 | 4.35/5 |
| Vol 27 | 3.43/5 | 4.34/5 |
| Overall | 3.28/5 | 4.43/5 |