condition mean min max ZT0-3 691.770518 691.770518 691.770518 ZT4-7 363.8635285 363.8635285 363.8635285 ZT8-11 378.944033 378.944033 378.944033 ZT12-15 364.56805199999997 364.56805199999997 364.56805199999997 ZT16-19 775.601754 775.601754 775.601754 ZT20-23 835.3643179999999 835.3643179999999 835.3643179999999