condition mean min max ZT0-3 0.7670945 0.7670945 0.7670945 ZT4-7 1.2223199999999999 1.2223199999999999 1.2223199999999999 ZT8-11 0.408883 0.408883 0.408883 ZT12-15 0.7927 0.7927 0.7927 ZT16-19 1.3181735 1.3181735 1.3181735 ZT20-23 1.202887 1.202887 1.202887