Given a text passage, come up with an appropriate title for it. The title should accurately represent what the main focus of the passage is. The title of a passage may be present in the first few sentences of the passage and/or be referred to multiple times in the passage. The title should be 1-5 words long.

Puerto Rico ( Spanish for `` Rich Port '' ) , officially the Commonwealth of Puerto Rico ( Spanish : Estado Libre Asociado de Puerto Rico , lit . `` Free Associated State of Puerto Rico '' ) and briefly called Porto Rico , is an unincorporated territory of the United States located in the northeast Caribbean Sea , approximately 1,000 miles ( 1,600 km ) southeast of Miami , Florida .
Puerto Rico

The International Monetary Fund ( IMF ) is an international organization headquartered in Washington , D.C. , consisting of `` 189 countries working to foster global monetary cooperation , secure financial stability , facilitate international trade , promote high employment and sustainable economic growth , and reduce poverty around the world . '' Formed in 1945 at the Bretton Woods Conference primarily by the ideas of Harry Dexter White and John Maynard Keynes , it came into formal existence in 1945 with 29 member countries and the goal of reconstructing the international payment system . It now plays a central role in the management of balance of payments difficulties and international financial crises . Countries contribute funds to a pool through a quota system from which countries experiencing balance of payments problems can borrow money . As of 2016 , the fund had SDR 477 billion ( about $666 billion ) .
International Monetary Fund

Lens speed refers to the maximum aperture diameter , or minimum f - number , of a photographic lens . A lens with a larger maximum aperture ( that is , a smaller minimum f - number ) is called a `` fast lens '' because it can achieve the same exposure with a faster shutter speed . Conversely , a smaller maximum aperture ( larger minimum f - number ) is `` slow '' because it delivers less light intensity and requires a slower ( longer ) shutter speed .

Lens speed