condition mean min max ZT0-3 49.8 49.8 49.8 ZT4-7 12.5 12.5 12.5 ZT8-11 21.7 21.7 21.7 ZT12-15 57.75 57.75 57.75 ZT16-19 31.200000000000003 31.200000000000003 31.200000000000003 ZT20-23 26.950000000000003 26.950000000000003 26.950000000000003