condition mean min max ZT0-3 6.5 6.5 6.5 ZT4-7 31.0 31.0 31.0 ZT8-11 38.5 38.5 38.5 ZT12-15 7.0 7.0 7.0 ZT16-19 3.75 3.75 3.75 ZT20-23 27.700000000000003 27.700000000000003 27.700000000000003