condition mean min max ZT0-3 4.937635 4.937635 4.937635 ZT4-7 4.486165 4.486165 4.486165 ZT8-11 3.817235 3.817235 3.817235 ZT12-15 3.3653750000000002 3.3653750000000002 3.3653750000000002 ZT16-19 4.763294999999999 4.763294999999999 4.763294999999999 ZT20-23 4.801769999999999 4.801769999999999 4.801769999999999