condition mean min max ZT0-3 11.805043 11.805043 11.805043 ZT4-7 10.331858 10.331858 10.331858 ZT8-11 11.7562615 11.7562615 11.7562615 ZT12-15 11.044176 11.044176 11.044176 ZT16-19 11.541515 11.541515 11.541515 ZT20-23 12.020851 12.020851 12.020851