The study looked at how personal income tax in Ecuador affected income inequality from 2007 to 2011. They found that even though the tax system is designed to be fair, high-income individuals find ways to pay less tax than low-income individuals. This means that the tax system doesn't do much to reduce income inequality. The study also showed that high-income people pay lower effective tax rates than they should, with optimal tax rates for the richest 1% potentially being as high as 63%.