| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.64/5 | 4.24/5 |
| Vol 3-4 | 2.58/5 | 4.32/5 |
| Vol 5-6 | 2.95/5 | 4.67/5 |
| Vol 7-8 | 3.06/5 | 4.70/5 |
| Vol 9-10 | 3.42/5 | 4.74/5 |
| Vol 11-12 | 2.81/5 | 4.58/5 |
| Vol 13-14 | 2.77/5 | 4.57/5 |
| Vol 15-16 | 2.52/5 | 4.41/5 |
| Vol 17-18 | 2.89/5 | 4.60/5 |
| Vol 19-20 | 2.70/5 | 4.33/5 |
| Vol 21-22 | 2.80/5 | 4.65/5 |
| Vol 23-24 | 2.78/5 | 4.68/5 |
| Vol 25-26 | 2.84/5 | 4.63/5 |
| Overall | 2.86/5 | 4.74/5 |