condition mean min max ZT0-3 3.23953430725 3.1139141945 3.36515442 ZT4-7 6.81741092625 6.152359822 7.4824620305 ZT8-11 13.2805811675 12.439192125 14.12197021 ZT12-15 14.961329085 14.666480234999998 15.256177935 ZT16-19 15.21031972 14.411409615 16.009229825 ZT20-23 15.380781732500001 14.480478895 16.28108457