condition mean min max ZT0-3 1939.616672 1939.616672 1939.616672 ZT4-7 1114.7295 1114.7295 1114.7295 ZT8-11 1272.3765600000002 1272.3765600000002 1272.3765600000002 ZT12-15 1411.3882735 1411.3882735 1411.3882735 ZT16-19 2267.3642515 2267.3642515 2267.3642515 ZT20-23 2169.3863925 2169.3863925 2169.3863925