condition mean min max ZT0-3 10.477873 10.477873 10.477873 ZT4-7 9.410713 9.410713 9.410713 ZT8-11 9.002614 9.002614 9.002614 ZT12-15 9.177417 9.177417 9.177417 ZT16-19 9.4566 9.4566 9.4566 ZT20-23 9.647193000000001 9.647193000000001 9.647193000000001