condition mean min max ZT0-3 17.90615 17.4248 18.3875 ZT4-7 24.6441 24.6441 24.6441 ZT8-11 15.87915 15.87915 15.87915 ZT12-15 0 0 0 ZT16-19 23.7104 23.7104 23.7104 ZT20-23 26.05305 26.05305 26.05305