condition mean min max ZT0-3 135.617471 135.617471 135.617471 ZT4-7 158.862478 158.862478 158.862478 ZT8-11 144.83806149999998 144.83806149999998 144.83806149999998 ZT12-15 164.20881500000002 164.20881500000002 164.20881500000002 ZT16-19 153.89152 153.89152 153.89152 ZT20-23 160.5454415 160.5454415 160.5454415