condition mean min max ZT0-3 10.834063333333333 5.5047049999999995 15.6984 ZT4-7 8.896905 8.896905 8.896905 ZT8-11 10.036875 10.036875 10.036875 ZT12-15 24.38935 22.13985 26.638849999999998 ZT16-19 27.2833 27.2833 27.2833 ZT20-23 22.6963 22.6963 22.6963