condition mean min max ZT0-3 13.539661 13.539661 13.539661 ZT4-7 12.759356499999999 12.759356499999999 12.759356499999999 ZT8-11 12.4377995 12.4377995 12.4377995 ZT12-15 11.2271815 11.2271815 11.2271815 ZT16-19 13.6435325 13.6435325 13.6435325 ZT20-23 14.065583499999999 14.065583499999999 14.065583499999999