| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 3.40/5 | 4.62/5 |
| Vol 3-4 | 3.79/5 | 4.63/5 |
| Vol 5-6 | 3.66/5 | 4.65/5 |
| Vol 7-8 | 3.25/5 | 4.57/5 |
| Vol 9-10 | 3.30/5 | 4.58/5 |
| Vol 11-12 | 3.58/5 | 4.55/5 |
| Vol 13-14 | 3.46/5 | 4.60/5 |
| Vol 15-16 | 3.74/5 | 4.65/5 |
| Vol 17-18 | 3.26/5 | 4.52/5 |
| Vol 19-20 | 3.03/5 | 4.58/5 |
| Vol 21-22 | 3.35/5 | 4.57/5 |
| Vol 23-24 | 3.96/5 | 4.63/5 |
| Vol 25-26 | 3.60/5 | 4.55/5 |
| Vol 27 | 3.50/5 | 4.57/5 |
| Overall | 3.49/5 | 4.65/5 |