condition mean min max ZT0-3 4.31333 4.31333 4.31333 ZT4-7 3.3939399999999997 3.3939399999999997 3.3939399999999997 ZT8-11 2.0104159999999998 2.0104159999999998 2.0104159999999998 ZT12-15 2.54913 2.54913 2.54913 ZT16-19 4.301493333333333 4.301493333333333 4.301493333333333 ZT20-23 4.2730999999999995 4.2730999999999995 4.2730999999999995