condition mean min max ZT0-3 20.379375 18.1191 22.63965 ZT4-7 4.963475 4.963475 4.963475 ZT8-11 11.36075 11.36075 11.36075 ZT12-15 0 0 0 ZT16-19 8.83518 8.83518 8.83518 ZT20-23 14.475850000000001 14.475850000000001 14.475850000000001