condition mean min max ZT0-3 5.15 5.15 5.15 ZT4-7 8.1 8.1 8.1 ZT8-11 5.05 5.05 5.05 ZT12-15 21.099999999999998 21.099999999999998 21.099999999999998 ZT16-19 4.8 4.8 4.8 ZT20-23 8.15 8.15 8.15