It seems to me although Iran faced hash sanctions with SWIFT ban in 2012 and again in 2018, their GDP took a hit and dropped for two years and but rebounded again (even through Covid). From the chart it seems that Iran might have found ways to make the SWIFT sanctions (remember they also suffered from their sanctions like travel ban and oil export ban) less effective on them. I wonder how Iran mitigated the effect of the SWIFT sanctions.

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