On 15 September 1939 Menzies announced the formation of the Second Australian Imperial Force (AIF). This expeditionary force initially consisted of 20,000 men organised into an infantry division (the 6th Division) and auxiliary units. The AIF was institutionally separate from the CMF, which was legally restricted to service in Australia and its external territories, and was formed by raising new units rather than transferring CMF units. On 15 November, Menzies announced the reintroduction of conscription for home-defence service, effective 1 January 1940. Recruitment for the AIF was initially slow, but one in six men of military age had enlisted by March 1940 and a huge surge of volunteers came forward after the fall of France in June 1940. Men volunteered for the AIF for a range of reasons, with the most common being a sense of duty to defend Australia and the British Empire. In early 1940 each of the services introduced regulations which prohibited the enlistment of people not "substantially of European origin"; while these regulations were strictly enforced by the RAN and Army, the RAAF continued to accept small numbers of non-European Australians.The AIF's major units were raised between 1939 and 1941. The 6th Division formed during October and November 1939 and embarked for the Middle East in early 1940 to complete its training and to receive modern equipment after the British Government assured the Australian Government that Japan did not pose an immediate threat. The division was intended to join the British Expeditionary Force in France when its preparations were complete, but this did not eventuate as Axis forces conquered France before the division was ready. A further three AIF infantry divisions (the 7th Division, 8th Division and 9th Division) were raised in the first half of 1940, as well as a corps headquarters (I Corps) and numerous support and service units. All of these divisions and the majority of the support units deployed overseas during 1940 and 1941. An AIF armoured division (the 1st Armoured Division) was also raised in early 1941 but never left Australia.While the Government initially planned to deploy the entire RAAF overseas, it later decided to focus the force's resources on training aircrew to facilitate a massive expansion of Commonwealth air-power. In late 1939 Australia and the other Dominions established the Empire Air Training Scheme (EATS) to train large numbers of men for service in the British Royal Air Force (RAF) and in other Commonwealth air units. Almost 28,000 Australians eventually trained through EATS in schools in Australia, Canada and Rhodesia. While many of these men were posted to Australian Article XV squadrons, the majority served with British and other Dominion squadrons. Moreover, these nominally "Australian" squadrons did not come under RAAF control and Australians often made up a minority of their airmen. As the Australian Government had no effective control over the deployment of airmen trained through EATS, most Australian historians regard the scheme as having hindered the development of Australia's defence capability. Nevertheless, RAAF airmen trained through EATS represented about nine percent of all aircrew who fought for the RAF in the European and Mediterranean theatres and made an important contribution to Allied operations.

Question: How many men did the Second Australian Imperial Force originally start out with?
Answer: 20,000 men