A higher bracket changes only the next slice
Fill progressive bands one slice at a time and retire the myth that one higher bracket reprices all income.
Each band taxes only its own slice
A progressive schedule is a stack of slices. Each slice has a width and a rate, and total bracket tax is the sum of each slice's tax.
The marginal rate describes the next slice. The effective rate averages the modeled total across included gross income.
Find the first band that changes
Open the ordinary stack in both checkpoints. The earlier bands are identical; the change appears only at the top of the stack.
Calculation replay
Predict, change, inspect.
Can crossing a bracket make take-home income fall below the pre-raise amount in this income-tax model?
- 01Income
- 02Deduction
- 03Rates
- 04NIIT
- 05Payments
Calculation replay ready.
Scenario
Avery receives a raise while every other input stays fixed.
Increase wages by $2,000 across a modeled bracket boundary.
Read the baseline, make a prediction, then play the change.
- Gross income
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- Taxable income
- —
- Regular income tax
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- NIIT
- —
- Total tax
- —
- Balance
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Related references