condition mean min max ZT0-3 63.3 63.3 63.3 ZT4-7 7.6 7.6 7.6 ZT8-11 38.3 38.3 38.3 ZT12-15 30.15 30.15 30.15 ZT16-19 69.25 69.25 69.25 ZT20-23 41.4 41.4 41.4