condition mean min max ZT0-3 237.702767 237.702767 237.702767 ZT4-7 218.238005 218.238005 218.238005 ZT8-11 234.987752 234.987752 234.987752 ZT12-15 256.831636 256.831636 256.831636 ZT16-19 295.8937565 295.8937565 295.8937565 ZT20-23 306.6388545 306.6388545 306.6388545