condition mean min max ZT0-3 226.716121 226.716121 226.716121 ZT4-7 236.90364699999998 236.90364699999998 236.90364699999998 ZT8-11 236.998197 236.998197 236.998197 ZT12-15 283.8960685 283.8960685 283.8960685 ZT16-19 323.316983 323.316983 323.316983 ZT20-23 293.480173 293.480173 293.480173