condition mean min max ZT0-3 1.32687 1.32687 1.32687 ZT4-7 0.940868 0.940868 0.940868 ZT8-11 1.3499599999999998 1.3499599999999998 1.3499599999999998 ZT12-15 1.418545 1.418545 1.418545 ZT16-19 2.424505 2.424505 2.424505 ZT20-23 1.168095 1.168095 1.168095