About $200 billion is earned from coffee worldwide every year. The farmers who grow it see about 8% of that. The rest gets swallowed up along the way by trade houses, middlemen, and coffee giants shopping around for the lowest possible price.
And the unfair part: that price isn't set where the coffee grows. It's set on a commodity exchange in New York, by algorithms and people who never set foot on a coffee farm. So the person doing the hardest work has the least say in what their work is worth.