condition mean min max ZT0-3 5.12097 5.12097 5.12097 ZT4-7 3.715185 3.715185 3.715185 ZT8-11 1.850715 1.850715 1.850715 ZT12-15 3.49551 3.49551 3.49551 ZT16-19 3.5889949999999997 3.5889949999999997 3.5889949999999997 ZT20-23 7.16841 7.16841 7.16841