condition mean min max ZT0-3 4.2 4.2 4.2 ZT4-7 0.8 0.8 0.8 ZT8-11 12.05 12.05 12.05 ZT12-15 3.3 3.3 3.3 ZT16-19 1.9500000000000002 1.9500000000000002 1.9500000000000002 ZT20-23 4.550000000000001 4.550000000000001 4.550000000000001