 Proponents point out that the FairTax has different features than the Tauzin bill and that the study done by the NRF makes many adverse assumptions and does not take into account the removal of embedded tax costs or the inventory credit that refunds 23% of the cost of held inventory.The study, which represents supporters' worst-case scenario for a consumption tax, predicts that the economy will grow only 3% more in ten years than it would have under the income tax and that the increase in consumption will be 1.15% less in the first year relative to what it would have been under the income tax.The study concludes that consumption will be higher in the fourth year and every year thereafter than it would have been under the income tax.