condition mean min max ZT0-3 18.473963 18.473963 18.473963 ZT4-7 17.591033 17.591033 17.591033 ZT8-11 13.5474485 13.5474485 13.5474485 ZT12-15 28.956779 28.956779 28.956779 ZT16-19 15.7419775 15.7419775 15.7419775 ZT20-23 24.0674425 24.0674425 24.0674425