condition mean min max ZT0-3 27.448566666666668 22.75385 32.15485 ZT4-7 17.44715 17.44715 17.44715 ZT8-11 13.4895 13.4895 13.4895 ZT12-15 20.860225 19.37795 22.3425 ZT16-19 28.2953 28.2953 28.2953 ZT20-23 31.9244 31.9244 31.9244