condition mean min max ZT0-3 7.660317353 7.509566948 7.811067758 ZT4-7 6.86887120825 6.066187728 7.6715546885 ZT8-11 10.17583687375 8.902027605 11.4496461425 ZT12-15 6.325322115 4.7414655555 7.9091786745 ZT16-19 5.012514832 4.3154687925 5.7095608715 ZT20-23 6.465268612 5.690812412 7.239724812