condition mean min max ZT0-3 4.21591 4.21591 4.21591 ZT4-7 3.1286899999999997 3.1286899999999997 3.1286899999999997 ZT8-11 3.152195 3.152195 3.152195 ZT12-15 4.24107 4.24107 4.24107 ZT16-19 4.961815 4.961815 4.961815 ZT20-23 4.055345 4.055345 4.055345