condition mean min max ZT0-3 0.2170427 0.04906165 0.46242300000000003 ZT4-7 0.4128905 0.4128905 0.4128905 ZT8-11 0.2608841 0.2608841 0.2608841 ZT12-15 0.235605275 0.09876475 0.3724458 ZT16-19 0.31507399999999997 0.31507399999999997 0.31507399999999997 ZT20-23 0.07570185 0.07570185 0.07570185