Methodology matters a lot for tax estimates, and this analysis – which is based on hypothetical taxpayers – may overestimate the tax cut you get. The results are correct for the simple tax scenarios we’re laying out, but most Americans have some factor that complicates their tax situation and can result in lower overall tax burdens, leading to smaller changes when tax law is amended.

Analyses that use data from real taxpayers as their starting point – like the calculator put together by the New York Times – produce lower estimates. Other calculators like the one put together by the Wall Street Journal produce similar results to ours. For example, a household in D.C. filing jointly with two kids under 17, earning a total of $150,000 and itemizing $20,000 gets a tax cut of $3,796 in our analysis. Roughly equivalent inputs to the New York Times calculator produces an estimated range of a $1,020 to $3,280 cut, while the Wall Street Journal calculator – which is based on the less generous House bill – produces a cut of $3,230.

Many other caveats apply (see more detailed methodology below). We’re only looking at income from salaries, wages and tips. Taxpayers who earn business income but pay taxes on it through the individual tax code may benefit from major changes to the “pass through” tax rates, which is not accounted for above. We’re only focusing on changes to the major, most common deductions, not accounting for the removal of certain miscellaneous deductions like unreimbursed business expenses over 2% of AGI (similar deductions are still available for small business expenses). If your overall deduction relies heavily on these miscellaneous deductions, this calculator is likely overestimating how much you’ll be able to itemize under the new bill.

And the corners of the chart above are territory that very few taxpayers fall into. Here’s what the distribution actually looks like, according to sample data from the Census’ Current Population Survey.