condition mean min max ZT0-3 217.001288 217.001288 217.001288 ZT4-7 299.1684205 299.1684205 299.1684205 ZT8-11 305.3496995 305.3496995 305.3496995 ZT12-15 265.89846750000004 265.89846750000004 265.89846750000004 ZT16-19 258.7137845 258.7137845 258.7137845 ZT20-23 261.9015745 261.9015745 261.9015745