During the astonishing growth of the Navy during World War I, women were, for the first time, accepted into the Navy. These women enlisted into the yeoman rating and were designated with an (F) for female. They served with the aviation unit and with the Public Works departments at Great Lakes. During World War II, a female auxiliary group called Women Accepted for Voluntary Emergency Services (WAVES) was established to release men for service in other areas. Their jobs were mostly clerical in nature, although that would change by the end of the war. WAVES were assigned to Great Lakes for the first time on November 10, 1942. As World War II progressed, WAVES assumed an increasingly important role. They handled 80 percent of the Navy's mail, manned communications networks, assumed hospital duties, and became instructors in chemical warfare techniques, aviation gunnery, instrument flying, and parachute rigging.