condition mean min max ZT0-3 186.693595 186.693595 186.693595 ZT4-7 119.4642025 119.4642025 119.4642025 ZT8-11 119.951825 119.951825 119.951825 ZT12-15 163.0562895 163.0562895 163.0562895 ZT16-19 148.731536 148.731536 148.731536 ZT20-23 192.39302450000002 192.39302450000002 192.39302450000002