condition mean min max ZT0-3 61.55 61.55 61.55 ZT4-7 34.9 34.9 34.9 ZT8-11 33.300000000000004 33.300000000000004 33.300000000000004 ZT12-15 41.4 41.4 41.4 ZT16-19 51.150000000000006 51.150000000000006 51.150000000000006 ZT20-23 27.65 27.65 27.65