condition mean min max ZT0-3 2.2240866666666665 1.598325 3.03437 ZT4-7 4.37747 4.37747 4.37747 ZT8-11 5.60771 5.60771 5.60771 ZT12-15 6.745065 5.507975 7.9821550000000006 ZT16-19 8.333425 8.333425 8.333425 ZT20-23 3.6318850000000005 3.6318850000000005 3.6318850000000005