Use of Black Market premium (BMP) to Investigate the Changes of Exchange Rate on the Added-value of Industry

Instability of exchange actual rate increases the risk and uncertainty, decrease of investment, shortening of investment horizon, instability of financial markets, reduction of foreign trade, allocation of the resources to the non-productive activities, reduction of industry added value and the growth of production rate and economy. By using Black Market Premium, this paper tries to evaluate the exchange rate fluctuations and its deviations during 1971-2010 due to the importance of the exchange rate variations, and then survey the negative effects of these fluctuations and deviations on the surplus value of industry.