condition mean min max ZT0-3 8.935195 8.42935 9.44104 ZT4-7 9.855785000000001 9.855785000000001 9.855785000000001 ZT8-11 33.88065 33.88065 33.88065 ZT12-15 0 0 0 ZT16-19 29.12965 29.12965 29.12965 ZT20-23 15.19085 15.19085 15.19085