condition mean min max ZT0-3 14.95 14.95 14.95 ZT4-7 0.8 0.8 0.8 ZT8-11 2.55 2.55 2.55 ZT12-15 2.3499999999999996 2.3499999999999996 2.3499999999999996 ZT16-19 9.25 9.25 9.25 ZT20-23 9.3 9.3 9.3