The US has had a long history of imposing sanctions on Iran. Let's take a look at those measures, and their impact on the Iranian economy.

On May 8 last year, U.S. President Donald Trump overturned former president Barack Obama's biggest policy decision.

The U.S. officially withdrew from the 2015 Iran nuclear deal. Trump blamed Iran for continuing its military expansion and waging a proxy war in the Middle East, but it wasn't the first time the U.S. used the sanction weapon against Iran. 

The sanctions were imposed for the first time in November 1979 after the Cultural Revolution, and then were lifted after two years. The next wave of measures came in 1987, then again in 1995 and later on in 2006. Initially, the U.S. sanctions targeted Iranian investments in oil and gas but were expanded to commercial dealings and banking, among others. 

These sanctions were finally lifted in January 2016 after the signing of the Iran nuclear deal, but the relaxation was short-lived. Trump re-imposed them in August and November last year. Over the years, the Iranian governments have been able to withstand the pressure.

But how resilient is Iran's economy now? Here are some facts.

The International Monetary Fund expects Iran's economy to contract by more than 3 percent in 2019, after projecting a 4-percent growth months earlier.

According to IMF data, every year 150,000-180,000 educated Iranians leave the country. The number is considered one of the worst cases of brain drain. Unemployment too has sky-rocketed to around 30 percent, while inflation is over 35 percent. Iran's currency, the rial, has lost nearly 70 percent of its value against the U.S. dollar in the past 12 months.