condition mean min max ZT0-3 0.258169894 0.092724551 0.423615237 ZT4-7 3.0827600215000004 2.3090850975 3.8564349455 ZT8-11 4.93422375325 4.1667994335 5.701648073 ZT12-15 12.3696337245 9.828052694 14.911214755 ZT16-19 19.5811447275 15.291055020000002 23.871234434999998 ZT20-23 51.23665919 31.68419264 70.78912574