| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.47/5 | 4.03/5 |
| Vol 3-4 | 2.40/5 | 4.17/5 |
| Vol 5-6 | 2.52/5 | 4.14/5 |
| Vol 7-8 | 2.60/5 | 4.30/5 |
| Vol 9-10 | 2.57/5 | 4.27/5 |
| Vol 11-12 | 2.58/5 | 4.19/5 |
| Vol 13-14 | 2.79/5 | 4.44/5 |
| Vol 15-16 | 2.58/5 | 4.25/5 |
| Vol 17-18 | 2.52/5 | 4.33/5 |
| Vol 19-20 | 2.64/5 | 4.25/5 |
| Vol 21-22 | 2.76/5 | 4.40/5 |
| Vol 23-24 | 2.70/5 | 4.41/5 |
| Vol 25-26 | 2.62/5 | 4.30/5 |
| Vol 27-28 | 2.48/5 | 4.17/5 |
| Overall | 2.59/5 | 4.44/5 |