condition mean min max ZT0-3 23.3446 23.3446 23.3446 ZT4-7 17.945999999999998 17.945999999999998 17.945999999999998 ZT8-11 17.697699999999998 17.697699999999998 17.697699999999998 ZT12-15 22.00155 22.00155 22.00155 ZT16-19 21.24035 21.24035 21.24035 ZT20-23 20.912399999999998 20.912399999999998 20.912399999999998