Two crucial events in the early 1970s spurred the economic development of the emirate. One was reaching independence and the establishment of the federation in 1971. The other was the oil crisis in 1973, which saw a large rise in oil revenues and helped the state finances. The emirate has continuously contributed to the GDP of the United Arab Emirates. The economy has since tried to move away from the traditional oil-based commodities to branch out into services such as transport and logistics. Dubai's tourism contributes a large part of its Gross Domestic Product (GDP) estimates.