condition mean min max ZT0-3 1043.456185 1043.456185 1043.456185 ZT4-7 1225.626992 1225.626992 1225.626992 ZT8-11 1198.182352 1198.182352 1198.182352 ZT12-15 984.790686 984.790686 984.790686 ZT16-19 757.0961445 757.0961445 757.0961445 ZT20-23 451.5124505 451.5124505 451.5124505