condition mean min max ZT0-3 5.0 5.0 5.0 ZT4-7 1.5 1.5 1.5 ZT8-11 4.45 4.45 4.45 ZT12-15 4.85 4.85 4.85 ZT16-19 4.800000000000001 4.800000000000001 4.800000000000001 ZT20-23 3.55 3.55 3.55