condition mean min max ZT0-3 4.8968525 4.778995 5.01471 ZT4-7 4.004595 4.004595 4.004595 ZT8-11 4.9640249999999995 4.9640249999999995 4.9640249999999995 ZT12-15 0 0 0 ZT16-19 6.884245 6.884245 6.884245 ZT20-23 5.870095 5.870095 5.870095