condition mean min max ZT0-3 1250.504831 1250.504831 1250.504831 ZT4-7 862.00865 862.00865 862.00865 ZT8-11 612.9978265 612.9978265 612.9978265 ZT12-15 647.1378970000001 647.1378970000001 647.1378970000001 ZT16-19 987.4904710000001 987.4904710000001 987.4904710000001 ZT20-23 1160.161341 1160.161341 1160.161341