condition mean min max ZT0-3 35.033699999999996 34.419 36.2269 ZT4-7 21.221449999999997 21.221449999999997 21.221449999999997 ZT8-11 14.3502 14.3502 14.3502 ZT12-15 17.227675 15.80755 18.6478 ZT16-19 20.8444 20.8444 20.8444 ZT20-23 31.308799999999998 31.308799999999998 31.308799999999998