condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0 0.0 0.0 ZT8-11 2.260565 2.260565 2.260565 ZT12-15 4.5469825 0.0 9.093965 ZT16-19 4.20766 4.20766 4.20766 ZT20-23 4.748545 4.748545 4.748545