condition mean min max ZT0-3 12.762741 12.762741 12.762741 ZT4-7 11.921266500000002 11.921266500000002 11.921266500000002 ZT8-11 12.224984 12.224984 12.224984 ZT12-15 12.811359 12.811359 12.811359 ZT16-19 14.183971499999998 14.183971499999998 14.183971499999998 ZT20-23 16.0991075 16.0991075 16.0991075