condition mean min max ZT0-3 21.5 21.5 21.5 ZT4-7 17.5 17.5 17.5 ZT8-11 25.65 25.65 25.65 ZT12-15 7.1 7.1 7.1 ZT16-19 23.549999999999997 23.549999999999997 23.549999999999997 ZT20-23 5.25 5.25 5.25