condition mean min max ZT0-3 40.849999999999994 40.849999999999994 40.849999999999994 ZT4-7 39.2 39.2 39.2 ZT8-11 19.55 19.55 19.55 ZT12-15 21.35 21.35 21.35 ZT16-19 12.5 12.5 12.5 ZT20-23 37.5 37.5 37.5