condition mean min max ZT0-3 24.147607 24.147607 24.147607 ZT4-7 26.803505 26.803505 26.803505 ZT8-11 20.582307 20.582307 20.582307 ZT12-15 21.9081685 21.9081685 21.9081685 ZT16-19 21.425569 21.425569 21.425569 ZT20-23 22.760303999999998 22.760303999999998 22.760303999999998