condition mean min max ZT0-3 64.7 64.7 64.7 ZT4-7 9.4 9.4 9.4 ZT8-11 27.25 27.25 27.25 ZT12-15 45.65 45.65 45.65 ZT16-19 22.2 22.2 22.2 ZT20-23 21.45 21.45 21.45