condition mean min max ZT0-3 11.744046 11.744046 11.744046 ZT4-7 11.9458285 11.9458285 11.9458285 ZT8-11 11.370728 11.370728 11.370728 ZT12-15 11.302219000000001 11.302219000000001 11.302219000000001 ZT16-19 13.058810000000001 13.058810000000001 13.058810000000001 ZT20-23 13.2665185 13.2665185 13.2665185