condition mean min max ZT0-3 7.39357 7.39357 7.39357 ZT4-7 6.927175 6.927175 6.927175 ZT8-11 9.672395 9.672395 9.672395 ZT12-15 8.235205 8.235205 8.235205 ZT16-19 9.730265 9.730265 9.730265 ZT20-23 7.3688899999999995 7.3688899999999995 7.3688899999999995