100% profits with fantastic four (00, 20, 50, 80)

[e.g., free flow of goods, services and capital] which seldom hold true in the real world.
Balance of payments model: This model, however, focuses largely on tradable

goods and services, ignoring the increasing role of global capital flows. It failed to provide any explanation for continuous appreciation of dollar during the 1980s and most part of the 1990s in face of soaring US current account deficit.

Asset market model: views currencies as an important asset class for constructing investment portfolios. Assets prices are influenced mostly by people's willingness to hold the existing quantities of assets, which in turn depends

on their expectations on the future worth of these assets. The asset market model of exchange rate determination states that “the exchange rate between two currencies represents the price that just

balances the relative supplies of, and demand for, assets denominated in those currencies.”
None of the models developed so far succeed to explain exchange rates and volatility in the longer time frames.

For shorter time frames (less than a few days) algorithms can be devised to predict prices. It is understood from the above models that many macroeconomic factors affect the exchange rates and in the end currency prices

are a result of dual forces of demand and supply. The world's currency markets can be viewed as a huge melting pot: in a large and ever-changing mix of current events, supply and demand factors are

constantly shifting, and the price of one currency in relation to another shifts accordingly. No other market encompasses (and distills) as much of what is going on in the world at any given time as foreign exchange.[72]

Supply and demand for any given currency, and thus its value, are not influenced by any single element, but rather by several. These elements generally fall into three categories: economic factors, political conditions and market psychology.

Economic factors[edit]
These include: (a) economic policy, disseminated by government agencies and central banks, (b) economic conditions, generally

revealed through economic reports, and other economic indicators.

Economic policy comprises government fiscal policy (budget/spending practices)

and monetary policy (the means by which a government's central bank influences the supply and "cost" of money, which is reflected by the level of interest rates).

Government budget deficits or surpluses: The market usually reacts negatively to widening government budget deficits, and positively to narrowing budget deficits. The impact is reflected in the value of a country's currency.
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nce of trade levels and trends: The trade flow between countries illustrates the demand for goods and services, which in turn indicates demand for a country's currency to conduct trade. Surpluses and deficits in trade of goods and services

reflect the competitiveness of a nation's economy. For example, trade deficits may have a negative impact on a nation's currency.
Inflation levels and trends: Typically a currency will lose value if there is a high level of inflation in the country or if inflation