condition mean min max ZT0-3 5.55 5.55 5.55 ZT4-7 17.8 17.8 17.8 ZT8-11 4.15 4.15 4.15 ZT12-15 6.35 6.35 6.35 ZT16-19 10.75 10.75 10.75 ZT20-23 5.8 5.8 5.8