condition mean min max ZT0-3 0.7157908333333334 0.2040635 1.19549 ZT4-7 0.48413700000000004 0.48413700000000004 0.48413700000000004 ZT8-11 0.620943 0.620943 0.620943 ZT12-15 1.32481725 0.5631695 2.086465 ZT16-19 2.2128699999999997 2.2128699999999997 2.2128699999999997 ZT20-23 2.171995 2.171995 2.171995