condition mean min max ZT0-3 146.435469 146.435469 146.435469 ZT4-7 222.117066 222.117066 222.117066 ZT8-11 231.05276700000002 231.05276700000002 231.05276700000002 ZT12-15 172.6206195 172.6206195 172.6206195 ZT16-19 216.5776705 216.5776705 216.5776705 ZT20-23 219.567827 219.567827 219.567827