Through the history and since 1933, the Iranian rial has declined from 11.2 rials per dollar to almost 8600 rials per dollar today in the parallel or black market. At the same time the official rate has been kept at artificial level most of the time, not consistent with other macro conditions of the country. Historically, however, the Central bank has adjusted the official rate and brought it in-line with the black market rate. This paper not only reviews the historical developments surrounding Iranian rial, but also provides an event study supporting the literature that any foreign exchange control has only short-nm impact on the official exchange rate. In the long-run, the official rate must be adjusted toward the black market rate, as evidenced by the behavior of the Central Bank of Iran
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