condition mean min max ZT0-3 14.65 14.65 14.65 ZT4-7 20.6 20.6 20.6 ZT8-11 27.5 27.5 27.5 ZT12-15 16.75 16.75 16.75 ZT16-19 15.0 15.0 15.0 ZT20-23 15.65 15.65 15.65