condition mean min max ZT0-3 0.109684 0.0 0.219368 ZT4-7 1.96827 1.96827 1.96827 ZT8-11 0.4466065 0.4466065 0.4466065 ZT12-15 0 0 0 ZT16-19 0.2162985 0.2162985 0.2162985 ZT20-23 0.433921 0.433921 0.433921