condition mean min max ZT0-3 2.6822999999999997 2.64857 2.71603 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0 0 0 ZT16-19 2.667995 2.667995 2.667995 ZT20-23 0.0 0.0 0.0