In economics terms, a decline in trade and general prosperity is called depression.

The great depression of 1929-34 was worldwide, starting with an agricultural recession followed by financial panic and collapse, known as the Wall Street Crash (Oct 1929) , in the USA

, in the USA The Wall Street crashes of late October 1929 — now known as Black Thursday, Black Monday and Black Tuesday — have often been seen as the beginning of what would become the Great Depression.

The effects on the USA were catastrophic: by 1933 almost 14 million people were out of work and American President Hoover’s efforts failed to make any impressions on crises.

Nobody was surprised when the Republicans lost the presidential election of Nov, 1932. The new Democrat President, Franklin D. Roosevelt, introduced policies known as the New Deal to try and put the country on the road to recovery.

The Great Depression is turn affected financial institutions and money markets in other parts of the world and caused a run on the pound in the UK. The result was a decline in internal consumption and exports in industrialized countries, factory closures, and massive unemployment.