condition mean min max ZT0-3 525.375823 525.375823 525.375823 ZT4-7 488.99690699999996 488.99690699999996 488.99690699999996 ZT8-11 360.0251495 360.0251495 360.0251495 ZT12-15 401.235569 401.235569 401.235569 ZT16-19 277.023513 277.023513 277.023513 ZT20-23 184.567275 184.567275 184.567275