condition mean min max ZT0-3 173.93576 173.93576 173.93576 ZT4-7 304.28321850000003 304.28321850000003 304.28321850000003 ZT8-11 298.495537 298.495537 298.495537 ZT12-15 326.3786875 326.3786875 326.3786875 ZT16-19 219.45941299999998 219.45941299999998 219.45941299999998 ZT20-23 164.61817250000001 164.61817250000001 164.61817250000001