condition mean min max ZT0-3 0.070311 0.070311 0.070311 ZT4-7 0.0519016 0.0519016 0.0519016 ZT8-11 0.0416042 0.0416042 0.0416042 ZT12-15 0.08763565 0.08763565 0.08763565 ZT16-19 0.0 0.0 0.0 ZT20-23 0.033870000000000004 0.033870000000000004 0.033870000000000004