condition mean min max ZT0-3 0.371909484 0.0 0.743818968 ZT4-7 0.67443858525 0.271779293 1.0770978775 ZT8-11 4.68772789775 0.0634628505 9.311992945 ZT12-15 27.5696352425 26.06301172 29.076258765 ZT16-19 29.597833103249997 22.144777796499998 37.05088841 ZT20-23 6.98239249925 4.211190883 9.7535941155