condition mean min max ZT0-3 68.2 68.2 68.2 ZT4-7 47.8 47.8 47.8 ZT8-11 36.9 36.9 36.9 ZT12-15 73.6 73.6 73.6 ZT16-19 63.849999999999994 63.849999999999994 63.849999999999994 ZT20-23 45.05 45.05 45.05