condition mean min max ZT0-3 20.75 20.75 20.75 ZT4-7 9.3 9.3 9.3 ZT8-11 38.8 38.8 38.8 ZT12-15 16.65 16.65 16.65 ZT16-19 16.1 16.1 16.1 ZT20-23 32.45 32.45 32.45