condition mean min max ZT0-3 114.638903 114.638903 114.638903 ZT4-7 77.205333 77.205333 77.205333 ZT8-11 76.7786875 76.7786875 76.7786875 ZT12-15 89.767132 89.767132 89.767132 ZT16-19 132.0293605 132.0293605 132.0293605 ZT20-23 161.5202585 161.5202585 161.5202585