condition mean min max ZT0-3 17.599516666666666 17.098399999999998 18.4939 ZT4-7 13.8889 13.8889 13.8889 ZT8-11 18.5088 18.5088 18.5088 ZT12-15 43.401700000000005 37.33065 49.472750000000005 ZT16-19 36.921850000000006 36.921850000000006 36.921850000000006 ZT20-23 25.557450000000003 25.557450000000003 25.557450000000003