condition mean min max ZT0-3 1.019829 1.019829 1.019829 ZT4-7 1.263135 1.263135 1.263135 ZT8-11 1.627585 1.627585 1.627585 ZT12-15 2.699955 2.699955 2.699955 ZT16-19 3.11601 3.11601 3.11601 ZT20-23 1.2950949999999999 1.2950949999999999 1.2950949999999999