condition mean min max ZT0-3 30.8549 26.9097 34.8001 ZT4-7 15.3056 15.3056 15.3056 ZT8-11 21.6298 21.6298 21.6298 ZT12-15 0 0 0 ZT16-19 27.411299999999997 27.411299999999997 27.411299999999997 ZT20-23 30.3018 30.3018 30.3018