condition mean min max ZT0-3 11.455081666666667 7.310345 14.440100000000001 ZT4-7 15.99175 15.99175 15.99175 ZT8-11 3.35243 3.35243 3.35243 ZT12-15 8.3796 5.57939 11.17981 ZT16-19 5.974489999999999 5.974489999999999 5.974489999999999 ZT20-23 6.04419 6.04419 6.04419