condition mean min max ZT0-3 0.331859 0.331859 0.331859 ZT4-7 0.2971355 0.2971355 0.2971355 ZT8-11 0.29969250000000003 0.29969250000000003 0.29969250000000003 ZT12-15 0.42874899999999994 0.42874899999999994 0.42874899999999994 ZT16-19 0.171885 0.171885 0.171885 ZT20-23 0.261409 0.261409 0.261409