condition mean min max ZT0-3 219.394513 219.394513 219.394513 ZT4-7 172.325553 172.325553 172.325553 ZT8-11 187.60364199999998 187.60364199999998 187.60364199999998 ZT12-15 194.98998999999998 194.98998999999998 194.98998999999998 ZT16-19 259.250827 259.250827 259.250827 ZT20-23 291.76005250000003 291.76005250000003 291.76005250000003