| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 2.86/5 | 4.55/5 |
| Vol 3-4 | 2.70/5 | 4.42/5 |
| Vol 5-6 | 3.62/5 | 4.62/5 |
| Vol 7-8 | 3.34/5 | 4.60/5 |
| Vol 9-10 | 3.64/5 | 4.62/5 |
| Vol 11-12 | 2.96/5 | 4.55/5 |
| Vol 13-14 | 4.00/5 | 4.63/5 |
| Vol 15-16 | 3.46/5 | 4.57/5 |
| Vol 17-18 | 3.14/5 | 4.51/5 |
| Vol 19-20 | 3.38/5 | 4.59/5 |
| Vol 21-22 | 2.96/5 | 4.50/5 |
| Vol 23-24 | 3.28/5 | 4.54/5 |
| Vol 25-26 | 3.20/5 | 4.55/5 |
| Vol 27-28 | 3.31/5 | 4.53/5 |
| Vol 29-30 | 3.88/5 | 4.59/5 |
| Vol 31 | 4.12/5 | 4.65/5 |
| Overall | 3.34/5 | 4.65/5 |