condition mean min max ZT0-3 5.35 5.35 5.35 ZT4-7 6.6 6.6 6.6 ZT8-11 17.35 17.35 17.35 ZT12-15 12.6 12.6 12.6 ZT16-19 12.05 12.05 12.05 ZT20-23 4.65 4.65 4.65