Deflation
Deflation occurred periodically in the U.S. during the 19th century (the most important exception was during the Civil War). This deflation was at times caused by technological progress that created significant economic growth, but at other times it was triggered by financial crises — notably the Panic of 1837 which caused deflation through 1844, and the Panic of 1873 which triggered the Long Depression that lasted until 1879. These deflationary periods preceded the establishment of the U.S. Federal Reserve System and its active management of monetary matters. Episodes of deflation have been rare and brief since the Federal Reserve was created (a notable exception being the Great Depression) while U.S. economic progress has been unprecedented.
Economic history of the United States
The Great Recession was a sharp decline in the United States' economy. In 2008, a series of related economic disasters hit the American and European financial systems. The bursting of a worldwide bubble in housing set the recession in motion. The end of housing bubbles in California, Florida and Arizona led to the collapse of housing prices and the shrinkage of construction sector. Millions of mortgages (averaging about $200,000 each) had been bundled into securities called collateralized debt obligations that were resold worldwide. Many banks and hedge funds had borrowed hundreds of billions of dollars to buy these securities, which were now "toxic" because their value was unknown and no one wanted to buy them.