condition mean min max ZT0-3 171.847441 171.847441 171.847441 ZT4-7 230.2299825 230.2299825 230.2299825 ZT8-11 205.616172 205.616172 205.616172 ZT12-15 211.3482105 211.3482105 211.3482105 ZT16-19 182.3973785 182.3973785 182.3973785 ZT20-23 223.18402550000002 223.18402550000002 223.18402550000002