condition mean min max ZT0-3 4.5885 4.5885 4.5885 ZT4-7 2.784825 2.784825 2.784825 ZT8-11 2.8639 2.8639 2.8639 ZT12-15 3.48095 3.48095 3.48095 ZT16-19 2.93232 2.93232 2.93232 ZT20-23 4.27999 4.27999 4.27999