Puerto Rico was placed under court protection on Wednesday in what amounts to the largest-ever U.S. municipal bankruptcy, a stark illustration of the depth of the economic crisis afflicting a U.S. territory with more than three million inhabitants.

Puerto Rico and its agencies owe $73 billion to creditors, dwarfing the roughly $9 billion in bond debt owed by the city of Detroit when it entered what was previously the largest municipal bankruptcy in 2013.

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