Economic bubble in the context of "Demand-side economics"

A financial crisis is any of a broad variety of situations in which some financial assets suddenly lose a large part of their nominal value. A broader reduction of economic activity affecting the whole economy is known as an economic crisis. In the 19th and early 20th centuries, many financial crises were associated with banking panics, and many recessions coincided with these panics. Other situations that are often called financial crises include stock market crashes and the bursting of other financial bubbles, currency crises, and sovereign defaults. Financial crises directly result in a loss of paper wealth but do not necessarily result in significant changes in the real economy (for example, the crisis resulting from the famous tulip mania bubble in the 17th century).

Many economists have offered theories about how financial crises develop and how they could be prevented. There is little consensus and financial crises continue to occur from time to time. It is apparent however that a consistent feature of both economic (and other applied finance disciplines) is the obvious inability to predict and avert financial crises. This realization raises the question as to what is known and also capable of being known (i.e. the epistemology) within economics and applied finance. It has been argued that the assumptions of unique, well-defined causal chains being present in economic thinking, models and data, could, in part, explain why financial crises are often inherent and unavoidable.

In economics, a recession is a business cycle contraction that occurs when there is a period of broad decline in economic activity. Recessions generally occur when there is a widespread drop in spending (an adverse demand shock). This may be triggered by various events, such as a financial crisis, an external trade shock, an adverse supply shock, the bursting of an economic bubble, or a large-scale anthropogenic or natural disaster (e.g. a pandemic). There is no official definition of a recession, according to the International Monetary Fund.

In the United States, a recession is defined as "a significant decline in economic activity spread across the market, lasting more than a few months, normally visible in real GDP, real income, employment, industrial production, and wholesale-retail sales." The European Union has adopted a similar definition. In the United Kingdom and Canada, a recession is defined as negative economic growth for two consecutive quarters.

A stock market crash is a sudden dramatic decline of stock prices across a major cross-section of a stock market, resulting in a significant loss of paper wealth. Crashes are driven by panic selling and underlying economic factors. They often follow speculation and economic bubbles.

A stock market crash is a social phenomenon where external economic events combine with crowd psychology in a positive feedback loop where selling by some market participants drives more market participants to sell. Generally speaking, crashes usually occur under the following conditions: a prolonged period of rising stock prices (a bull market) and excessive economic optimism, a market where price–earnings ratios exceed long-term averages, and extensive use of margin debt and leverage by market participants. Other aspects such as wars, large corporate hacks, changes in federal laws and regulations, and natural disasters within economically productive areas may also influence a significant decline in the stock market value of a wide range of stocks. Stock prices for corporations competing against the affected corporations may rise despite the crash.

The Japanese asset price bubble (バブル景気, baburu keiki; lit. 'bubble economy') was an economic bubble in Japan from 1986 to 1991 in which real estate and stock market prices were greatly inflated. In early 1992, this price bubble burst and the country's economy stagnated. The bubble was characterized by rapid acceleration of asset prices and overheated economic activity, as well as an uncontrolled money supply and credit expansion. More specifically, over-confidence and speculation regarding asset and stock prices were closely associated with excessive monetary easing policy at the time. Through the creation of economic policies that cultivated the marketability of assets, eased the access to credit, and encouraged speculation, the Japanese government started a prolonged and exacerbated Japanese asset price bubble.

By August 1990, the Nikkei stock index had plummeted to half its peak by the time of the fifth monetary tightening by the Bank of Japan (BOJ). By late 1991, other asset prices began to fall. Even though asset prices had visibly collapsed by early 1992, the economy's decline continued for more than a decade. This decline resulted in a huge accumulation of non-performing assets loans (NPL), causing difficulties for many financial institutions. The bursting of the Japanese asset price bubble contributed to what many call the Lost Decade. Japan's average nationwide land prices finally began to increase year-over-year in 2018, with a 0.1% rise over 2017 price levels.