| Progress | Difficulty | Peak |
|---|---|---|
| Vol 1-2 | 1.70/5 | 4.25/5 |
| Vol 3-4 | 1.80/5 | 4.25/5 |
| Vol 5-6 | 1.78/5 | 4.35/5 |
| Vol 7-8 | 2.02/5 | 4.32/5 |
| Vol 9-10 | 2.20/5 | 4.36/5 |
| Vol 11-12 | 1.91/5 | 4.33/5 |
| Vol 13-14 | 2.42/5 | 4.48/5 |
| Vol 15-16 | 1.86/5 | 4.43/5 |
| Vol 17-18 | 1.98/5 | 4.35/5 |
| Vol 19-20 | 2.58/5 | 4.52/5 |
| Vol 21-22 | 2.13/5 | 4.43/5 |
| Vol 23-24 | 1.94/5 | 4.45/5 |
| Vol 25-26 | 1.83/5 | 4.34/5 |
| Vol 27-28 | 1.75/5 | 4.21/5 |
| Vol 29-30 | 1.90/5 | 4.17/5 |
| Vol 31-32 | 2.44/5 | 4.42/5 |
| Vol 33-34 | 2.28/5 | 4.46/5 |
| Vol 35-36 | 1.85/5 | 4.40/5 |
| Vol 37-38 | 1.60/5 | 4.32/5 |
| Vol 39-40 | 2.08/5 | 4.40/5 |
| Vol 41-42 | 2.24/5 | 4.42/5 |
| Vol 43-44 | 2.44/5 | 4.48/5 |
| Vol 45-46 | 2.38/5 | 4.45/5 |
| Vol 47-48 | 2.56/5 | 4.50/5 |
| Vol 49-50 | 2.16/5 | 4.39/5 |
| Overall | 2.07/5 | 4.52/5 |