condition mean min max ZT0-3 28.626266666666666 17.60625 34.862849999999995 ZT4-7 9.620685 9.620685 9.620685 ZT8-11 5.964285 5.964285 5.964285 ZT12-15 16.977975 14.9083 19.047649999999997 ZT16-19 19.935850000000002 19.935850000000002 19.935850000000002 ZT20-23 33.688649999999996 33.688649999999996 33.688649999999996