condition mean min max ZT0-3 6.226015 6.226015 6.226015 ZT4-7 6.170165 6.170165 6.170165 ZT8-11 2.2729299999999997 2.2729299999999997 2.2729299999999997 ZT12-15 1.67821 1.67821 1.67821 ZT16-19 4.82277 4.82277 4.82277 ZT20-23 5.4057949999999995 5.4057949999999995 5.4057949999999995