condition mean min max ZT0-3 163.347817 163.347817 163.347817 ZT4-7 203.18478349999998 203.18478349999998 203.18478349999998 ZT8-11 184.72031299999998 184.72031299999998 184.72031299999998 ZT12-15 192.76925749999998 192.76925749999998 192.76925749999998 ZT16-19 227.5874285 227.5874285 227.5874285 ZT20-23 177.613182 177.613182 177.613182