condition mean min max ZT0-3 1.1081737947499999 0.0 2.2163475894999998 ZT4-7 7.39833746425 6.0455889885000005 8.75108594 ZT8-11 12.16273054325 11.7999205655 12.525540521 ZT12-15 15.034009115 14.211829135 15.856189095 ZT16-19 19.7758081925 19.44349716 20.108119225 ZT20-23 13.14426535875 10.8928882475 15.395642469999999