condition mean min max ZT0-3 1.89707475 1.7924845 2.001665 ZT4-7 2.023035 2.023035 2.023035 ZT8-11 0.796863 0.796863 0.796863 ZT12-15 0 0 0 ZT16-19 1.375959 1.375959 1.375959 ZT20-23 1.37825 1.37825 1.37825