Iran's currency has lost half its value since April 2018

Daily Mail:

Iran's currency is continuing its downward spiral as increased American sanctions loom, hitting a new low on the thriving black market exchange.

On Sunday, the Iranian rial plunged to a low of 111,500 against one U.S. dollar on the unofficial market, down from about 97,500 rials on Saturday, according to foreign exchange website Bonbast.com.

Other websites said the dollar was exchanged between 108,500 and 116,000 rials.

The rial has lost about half of its value since April because of a weak economy, financial difficulties at local banks and heavy demand for dollars among Iranians who fear the effects of sanctions.

In May the United States pulled out of a 2015 deal between world powers and Tehran under which international sanctions on Iran were lifted in return for curbs on its nuclear program.
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On Aug. 7, the United States will reimpose sanctions on the purchase or acquisition of U.S. dollars by the Iranian government, Iran’s trade in gold and precious metals, and on the direct and indirect sale, supply and transfer to or from Iran of graphite, raw or semi-finished metals, coal and industrial-related software.

Sanctions also will be reapplied to the importation into the United States of carpets and foodstuffs made in Iran, and on certain related financial transactions.

Iran’s oil exports could fall by as much as two-thirds by the end of the year because of the new U.S. sanctions, putting oil markets under huge strain amid supply outages elsewhere in the world.

Iran made the mistake of squandering their windfall from Obama's deal on proxy forces outside the country rather than investing in the people.  It has had the dramatic effect of plummeting support for the regime and leaving it without many resources to deal with Trump's reimposition of sanctions.  As much as Europe may like to keep the deal going, their companies can't afford to take the risk of not being able to do business with the US.