condition mean min max ZT0-3 1.9958275 1.957275 2.03438 ZT4-7 3.433995 3.433995 3.433995 ZT8-11 3.32198 3.32198 3.32198 ZT12-15 0 0 0 ZT16-19 3.0131750000000004 3.0131750000000004 3.0131750000000004 ZT20-23 2.847445 2.847445 2.847445