condition mean min max ZT0-3 31.465044 31.465044 31.465044 ZT4-7 34.5612355 34.5612355 34.5612355 ZT8-11 34.010926 34.010926 34.010926 ZT12-15 27.350421500000003 27.350421500000003 27.350421500000003 ZT16-19 37.1902255 37.1902255 37.1902255 ZT20-23 34.396733499999996 34.396733499999996 34.396733499999996