Q. Black market exchange rates?

Black market exchange rates are exchange rates that differ from the officially given exchange rate set by a government.  These black market rates often occur when the official rate bears little resemblance to the actual market conditions. 

• Global Financial Data
  • Time series of black market exchange rates for about 50 countries.  Largely historic but some are fairly up to date including for North Korea and Venezuela.
  • Click the "GFD Search Engines" button. 
  • In the left-side column, under "Series Type," choose "Exchange Rates - Black Market" from the drop-down menu.
• Datastream – for Iran and Venezuela
• Exchange Rates (Official and Parallel) - Carmen M. Reinhart - Harvard University.data through 2016
• Gramacy, R., Malone, S. W., & Horst, E. T. (2014). Exchange rate fundamentals, forecasting, and speculation: Bayesian models in black markets. Journal of Applied Econometrics, 29(1), 22-41.  This research uses a dataset on black market rates, including determinants, and contains the official rate for constructing the black market premium.  Coverage varies by nation, and appears to range from 1963 to 2009.
• For Iran, see the Central Bank of Iran's Time Series Database. – for annual data. Choose the category External Sector - then "Value of Financial Assets (Exchange Rate & Coin Price"- then exchange rates- under both US Dollar and Euro, you will find "Non-official Rate". From 1978-2018.
• For Egypt, the Daily News features regular stories on the black market