condition mean min max ZT0-3 29.30605 29.30605 29.30605 ZT4-7 23.986449999999998 23.986449999999998 23.986449999999998 ZT8-11 21.717550000000003 21.717550000000003 21.717550000000003 ZT12-15 20.0914 20.0914 20.0914 ZT16-19 23.261400000000002 23.261400000000002 23.261400000000002 ZT20-23 24.5768 24.5768 24.5768