condition mean min max ZT0-3 3.872775 3.537955 4.38591 ZT4-7 3.6100149999999998 3.6100149999999998 3.6100149999999998 ZT8-11 3.92801 3.92801 3.92801 ZT12-15 5.373895 4.048145 6.699645 ZT16-19 4.462545 4.462545 4.462545 ZT20-23 4.404645 4.404645 4.404645