condition mean min max ZT0-3 18.4 18.4 18.4 ZT4-7 6.4 6.4 6.4 ZT8-11 29.200000000000003 29.200000000000003 29.200000000000003 ZT12-15 22.3 22.3 22.3 ZT16-19 22.950000000000003 22.950000000000003 22.950000000000003 ZT20-23 43.4 43.4 43.4