condition mean min max ZT0-3 26.223140415000003 19.8074769 32.63880393 ZT4-7 19.06934615 16.344644345 21.794047955 ZT8-11 19.6697496475 18.197850205 21.14164909 ZT12-15 19.660367100000002 19.49642103 19.82431317 ZT16-19 15.8430107925 15.087704989999999 16.598316595 ZT20-23 21.814436735 21.52013589 22.10873758