condition mean min max ZT0-3 8.1295125 8.001515 8.25751 ZT4-7 9.896715 9.896715 9.896715 ZT8-11 12.65815 12.65815 12.65815 ZT12-15 0 0 0 ZT16-19 14.793299999999999 14.793299999999999 14.793299999999999 ZT20-23 8.693265 8.693265 8.693265