condition mean min max ZT0-3 0.5906968315 0.40616282600000003 0.775230837 ZT4-7 1.03364892325 0.8291117145 1.238186132 ZT8-11 1.4545893239999999 1.2231783319999998 1.6860003159999999 ZT12-15 2.2075369085 2.0204905745 2.3945832425 ZT16-19 1.83261156475 1.742283121 1.9229400085 ZT20-23 2.40672822175 2.3571338235 2.45632262