condition mean min max ZT0-3 0.239121 0.0 0.371582 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0.355355 0.0 0.71071 ZT16-19 0.0 0.0 0.0 ZT20-23 0.0 0.0 0.0