condition mean min max ZT0-3 33.7 33.7 33.7 ZT4-7 9.5 9.5 9.5 ZT8-11 31.75 31.75 31.75 ZT12-15 44.400000000000006 44.400000000000006 44.400000000000006 ZT16-19 34.75 34.75 34.75 ZT20-23 29.95 29.95 29.95