condition mean min max ZT0-3 23.549999999999997 23.549999999999997 23.549999999999997 ZT4-7 8.3 8.3 8.3 ZT8-11 28.9 28.9 28.9 ZT12-15 34.65 34.65 34.65 ZT16-19 11.8 11.8 11.8 ZT20-23 8.2 8.2 8.2