condition mean min max ZT0-3 12.9 12.9 12.9 ZT4-7 4.4 4.4 4.4 ZT8-11 5.45 5.45 5.45 ZT12-15 19.400000000000002 19.400000000000002 19.400000000000002 ZT16-19 12.5 12.5 12.5 ZT20-23 7.25 7.25 7.25