How Isis makes its money

In 2014, Isis made around $360 million via extortion and taxation in Iraq alone.

The figure is indicative of the terror group's policy of asset seizure and sale, to fund further conflict.

This policy is typified by the seizure of state-owned banks in northern and western Iraq last year, from which the US treasury department reports that Isis stole at least half a billion dollars.

As the below chart from Statista shows, Isis makes approximately $500 million from oil a year (some of which is counted towards its total for 'extortion'):

The figure for farmland revenue comes from a Thomson Reuters report, which found that crops from fertile, Isis-controlled lands in Iraq and Syria would still generate more than $200 million in annual income if sold at half price on the black market.

Meanwhile a UN Security Council report in 2014 found that Isis had made between $35 million and $45 million in kidnapping and ransom alone.

It should be noted that the annual revenue streams are not as constant as the monthly for this chart, and the figures are approximate estimates.

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