condition mean min max ZT0-3 7.881755 7.881755 7.881755 ZT4-7 4.266095 4.266095 4.266095 ZT8-11 5.813245 5.813245 5.813245 ZT12-15 5.941655 5.941655 5.941655 ZT16-19 15.782399999999999 15.782399999999999 15.782399999999999 ZT20-23 11.409199999999998 11.409199999999998 11.409199999999998