condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0 0.0 0.0 ZT8-11 2.411335 2.411335 2.411335 ZT12-15 1.172535 0.0 2.34507 ZT16-19 0.0 0.0 0.0 ZT20-23 2.626225 2.626225 2.626225