condition mean min max ZT0-3 0.530502 0.419647 0.641357 ZT4-7 2.148195 2.148195 2.148195 ZT8-11 0.8635995 0.8635995 0.8635995 ZT12-15 0 0 0 ZT16-19 0.41997 0.41997 0.41997 ZT20-23 0.633753 0.633753 0.633753