condition mean min max ZT0-3 893.078211 893.078211 893.078211 ZT4-7 1031.141969 1031.141969 1031.141969 ZT8-11 1419.971397 1419.971397 1419.971397 ZT12-15 1263.5500875 1263.5500875 1263.5500875 ZT16-19 1299.08866 1299.08866 1299.08866 ZT20-23 1061.428686 1061.428686 1061.428686