I’m sorry, I have troublr understanding your chart.
Starting with Adjusted gross income, then reducing that by charity giving and taxes should leave you with “spendable income”
Your charts take AGI and add tax and charity to arrive at to $ total kept.
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I have no idea what you are trying to accomplish.
If you have $100 in your pocket, give $20 to the church, then pay $10 in taxes, your $ total kept is $70, not $130 per your calculation.