If there were no tax breaks, subsidies, exemptions and all entities paid a flat rate of income tax?

... what percent of flat tax rate do you think would be equal to the amount of income tax contribution we have now? Also, exclude the impoverished as they contribute little in income tax as it is.
Update: ing- If you want to tax the impoverished ... then submit a number including that (as if it's going to make much difference).
Update 2: ... or submit a number that reflects both (w/ and w/o the impoverished contribution)
Update 3: Folks- The focus of my q is intended to concentrate on how the flat tax structure would reflect no more billions in subsidies to big oil ... no more tax exemptions for ANYONE. Imagine the increased revenue f/ the current tax exempt entities. That has to be millions/billions. Is there anyone out there able to... show more Folks- The focus of my q is intended to concentrate on how the flat tax structure would reflect no more billions in subsidies to big oil ... no more tax exemptions for ANYONE. Imagine the increased revenue f/ the current tax exempt entities. That has to be millions/billions.
Is there anyone out there able to address this q at face value?
What if churches were required to pay the same rate of flat income tax? Are you understanding my inquiry?
Update 4: If we started taxing all the income that currently is not taxed ... that will lower the amount the rest of us pay as I presented an equation to equal what the current income tax contribution is.
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