condition mean min max ZT0-3 13.461459 13.461459 13.461459 ZT4-7 12.204853499999999 12.204853499999999 12.204853499999999 ZT8-11 15.2271615 15.2271615 15.2271615 ZT12-15 13.727238 13.727238 13.727238 ZT16-19 12.225852 12.225852 12.225852 ZT20-23 11.692275500000001 11.692275500000001 11.692275500000001