condition mean min max ZT0-3 11.533945 11.533945 11.533945 ZT4-7 11.533945 11.533945 11.533945 ZT8-11 12.2685935 12.2685935 12.2685935 ZT12-15 11.9899785 11.9899785 11.9899785 ZT16-19 11.150121500000001 11.150121500000001 11.150121500000001 ZT20-23 11.8954265 11.8954265 11.8954265