condition mean min max ZT0-3 2.584625 2.584625 2.584625 ZT4-7 2.2667 2.2667 2.2667 ZT8-11 2.395885 2.395885 2.395885 ZT12-15 2.555435 2.555435 2.555435 ZT16-19 2.38795 2.38795 2.38795 ZT20-23 2.568255 2.568255 2.568255