condition mean min max ZT0-3 30.070875 29.67905 30.462699999999998 ZT4-7 31.92455 31.92455 31.92455 ZT8-11 28.2768 28.2768 28.2768 ZT12-15 0 0 0 ZT16-19 31.668499999999998 31.668499999999998 31.668499999999998 ZT20-23 30.67935 30.67935 30.67935