condition mean min max ZT0-3 71.851096 71.851096 71.851096 ZT4-7 72.559675 72.559675 72.559675 ZT8-11 67.4206805 67.4206805 67.4206805 ZT12-15 68.37077500000001 68.37077500000001 68.37077500000001 ZT16-19 78.924497 78.924497 78.924497 ZT20-23 68.082384 68.082384 68.082384