condition mean min max ZT0-3 16.536225 16.25195 16.820500000000003 ZT4-7 16.058799999999998 16.058799999999998 16.058799999999998 ZT8-11 17.58905 17.58905 17.58905 ZT12-15 0 0 0 ZT16-19 27.042749999999998 27.042749999999998 27.042749999999998 ZT20-23 18.0945 18.0945 18.0945