condition mean min max ZT0-3 12.172061 12.172061 12.172061 ZT4-7 12.1474935 12.1474935 12.1474935 ZT8-11 11.464911 11.464911 11.464911 ZT12-15 12.314909499999999 12.314909499999999 12.314909499999999 ZT16-19 13.344696500000001 13.344696500000001 13.344696500000001 ZT20-23 11.046503999999999 11.046503999999999 11.046503999999999