condition mean min max ZT0-3 16.906555 2.019915 30.5412 ZT4-7 1.89805 1.89805 1.89805 ZT8-11 5.226884999999999 5.226884999999999 5.226884999999999 ZT12-15 14.32744 11.41678 17.2381 ZT16-19 24.82945 24.82945 24.82945 ZT20-23 43.41445 43.41445 43.41445