condition mean min max ZT0-3 32.6 32.6 32.6 ZT4-7 63.0 63.0 63.0 ZT8-11 33.650000000000006 33.650000000000006 33.650000000000006 ZT12-15 29.549999999999997 29.549999999999997 29.549999999999997 ZT16-19 27.75 27.75 27.75 ZT20-23 42.900000000000006 42.900000000000006 42.900000000000006