Below is chart to show how the Iranian Rial has collapsed against the US dollar – in reading the graph it takes a significant number of Rial to buy a US dollar. Over the past week it has lost 40% of its value mainly as the western sanctions on oil exports start to bite. These were imposed because of Iran’s disputed nuclear programme. This also indicates that the Iranian central bank’s is finding it impossible to support its currency.
On 3rd October the currency traded at 36,100 though traders in Tehran said most foreign exchange centres have stopped trading in the US dollar. That compares with the official value of 12,260 rials per dollar set by the central bank. The chart below I got from the Business Insider website. It shows how many Rial it took to buy a dollar over the last 70 days. Note that on the Persian Calendar it’s the year 1391.