condition mean min max ZT0-3 40.65763333333334 29.32225 55.28315 ZT4-7 20.14165 20.14165 20.14165 ZT8-11 25.731099999999998 25.731099999999998 25.731099999999998 ZT12-15 40.827325 28.4265 53.22815 ZT16-19 35.71705 35.71705 35.71705 ZT20-23 57.90365 57.90365 57.90365