condition mean min max ZT0-3 3.10498 3.10498 3.10498 ZT4-7 1.74576 1.74576 1.74576 ZT8-11 2.16167 2.16167 2.16167 ZT12-15 2.73376 2.73376 2.73376 ZT16-19 5.217245 5.217245 5.217245 ZT20-23 3.616355 3.616355 3.616355