condition mean min max ZT0-3 4.34318 4.34318 4.34318 ZT4-7 2.78195 2.78195 2.78195 ZT8-11 2.03793 2.03793 2.03793 ZT12-15 3.293765 3.293765 3.293765 ZT16-19 7.868625 7.868625 7.868625 ZT20-23 5.80871 5.80871 5.80871