condition mean min max ZT0-3 23.200000000000003 23.200000000000003 23.200000000000003 ZT4-7 11.7 11.7 11.7 ZT8-11 47.7 47.7 47.7 ZT12-15 12.9 12.9 12.9 ZT16-19 8.15 8.15 8.15 ZT20-23 14.65 14.65 14.65