| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.52/5 | 3.86/5 |
| Vol 3-4 | 2.77/5 | 3.94/5 |
| Vol 5-6 | 2.74/5 | 3.86/5 |
| Vol 7-8 | 2.78/5 | 4.00/5 |
| Vol 9-10 | 2.74/5 | 3.74/5 |
| Vol 11-12 | 2.76/5 | 3.72/5 |
| Vol 13-14 | 2.64/5 | 3.40/5 |
| Vol 15-16 | 2.71/5 | 3.76/5 |
| Vol 17-18 | 2.64/5 | 3.50/5 |
| Vol 19-20 | 2.63/5 | 3.42/5 |
| Vol 21-22 | 2.64/5 | 3.44/5 |
| Vol 23-24 | 2.59/5 | 3.07/5 |
| Vol 25-26 | 2.68/5 | 3.63/5 |
| Vol 27-28 | 2.62/5 | 3.38/5 |
| Vol 29-30 | 2.60/5 | 3.33/5 |
| Vol 31-32 | 2.57/5 | 2.99/5 |
| Vol 33 | 2.66/5 | 3.59/5 |
| Overall | 2.66/5 | 4.00/5 |