condition mean min max ZT0-3 39.75 39.75 39.75 ZT4-7 24.1 24.1 24.1 ZT8-11 19.1 19.1 19.1 ZT12-15 25.8 25.8 25.8 ZT16-19 48.2 48.2 48.2 ZT20-23 73.9 73.9 73.9