| ZF difference | ZF0-ZF−1 | ZF1-ZF0 | ZF1-ZF−1 | ZF2-ZF1 | ZF2-ZF−1 | ZF3-ZF2 | ZF3-ZF−1 |
| Average value (%) | 0.03 | −0.03 | 1.9 | −0.03 | −0.06 | 0 | −2.25 |
| positive rate (%) | 51.52 | 51.52 | 60.61 | 36.36 | 57.58 | 51.52 | 48.48 |