condition mean min max ZT0-3 0.4509420833333333 0.18179375 0.6286885 ZT4-7 0.9754529999999999 0.9754529999999999 0.9754529999999999 ZT8-11 1.822025 1.822025 1.822025 ZT12-15 1.52901 1.386535 1.671485 ZT16-19 1.93933 1.93933 1.93933 ZT20-23 1.9068399999999999 1.9068399999999999 1.9068399999999999