condition mean min max ZT0-3 1.4810951817500002 1.226094229 1.7360961345 ZT4-7 2.27446225 1.9865208779999999 2.562403622 ZT8-11 3.5069076454999997 2.7335388079999996 4.280276483 ZT12-15 7.0742026525 5.1420828435 9.0063224615 ZT16-19 4.784824957 4.678359854 4.89129006 ZT20-23 5.517275933 4.8877428095 6.1468090564999995