condition mean min max ZT0-3 21.19305 18.3945 23.9916 ZT4-7 7.27389 7.27389 7.27389 ZT8-11 7.6125050000000005 7.6125050000000005 7.6125050000000005 ZT12-15 0 0 0 ZT16-19 11.48695 11.48695 11.48695 ZT20-23 14.74625 14.74625 14.74625