condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0.023674324833333333 0.022174716666666667 0.025173933 ZT16-19 0.0 0.0 0.0 ZT20-23 0.0 0.0 0.0