condition mean min max ZT0-3 23.85 23.85 23.85 ZT4-7 31.7 31.7 31.7 ZT8-11 38.75 38.75 38.75 ZT12-15 39.2 39.2 39.2 ZT16-19 32.349999999999994 32.349999999999994 32.349999999999994 ZT20-23 27.3 27.3 27.3