• Internet Taxsim (v7) is a subset of full TAXSIM which calculates federal and state income tax liabilities from survey data. You provide the data, the NBER TAXSIM program returns the tax calculations from our server in seconds. Covers 1960 - 2013 (federal) 1977 - 2005 (state). Please read the instructions carefully.
• Previous version
• Codes for creating Internet TAXSIM format datafiles from commonly used surveys.

  Documentation and Background

• PDF version of "An Introduction to the TAXSIM Model", by Daniel Feenberg and Elisabeth Coutts. From the Journal of Policy Analysis and Management Vol. 12 no. 1 (Winter, 1993).
• Statistics of Income Division (SOI) General Description Booklets for the Tax Model Files, with sources and descriptions for every variable in the disclosure proofed public release files.
• Concordance of fields in the SOI division public use files, showing the locations of variables through the years:
  • 1960-1979
  • 1979+
• Estate and Gift Tax Micro Data

  Tables from TAXSIM

• Marginal and Average Rates, and Elasticity of the Income Tax system - 1960 - 2005
• Marginal Tax Rates by Factor Income
  • Federal
  • Federal plus State
  • Rates by State
• US rates at constant real income levels.
• Auerbach and Feenberg on Automatic Stabilizers
• High Income Shares
• High Income Shares 1994 - 1996
• Tax rates by age.
• Chart of state by year allowance of a charitable deduction.
• Maximum State tax rates. 
• Sales Tax Tables.

Mailing list

These tables show the average marginal state income tax rate on various types of income over the years 1977 to 2004. Three approaches are taken. In one, actual micro data for each state and year is used, as supplied by the Statistics of Income Division of the IRS. In the second the same nationally representative sample from 1995 is used (properly deflated) for each state and year. This later approach allows for comparisons of law without confusing changes in income and deductions with changes in law. In some regression studies it may be used as an instrument for the actual tax rate that is independent of a state's economic condition. A final pair of tables use the actual distribution of income across states in 1995 for all years.

The calculation accounts for the cross deductibility of state and federal taxes for itemizers in certain states. Notice that in states with no deduction for mortgage interest paid but whose taxes depend in some manner on the federal tax (either directly or because of a deduction for federal taxes) this rate will be non-zero and may be positive or negative. The TAXSIM model used for these computations accounts for all the major and most minor features of the tax code, including minimum and maximum taxes, credits, phaseouts, and itemization status.

The calculation for each cell is done by first finding the sum of the income tax liabilities owed by all the taxpayers in that state for that year. Then we increase the selected income item by 1% for each taxpayer and recalculate the tax. The ratio of the additional tax to the additional income (multiplied by 100) is shown in the tables for 6 types of income.

Using the actual distribution of income by state.

The SOI division does not reveal the state of residence for taxpayers with AGI greater than $200,000 (nominal). We have the number of such taxpayers by state for most years since 1989, and use that information to impute states for high income taxpayers. All pre 1989 imputations use the 1989 distribution of taxpayers across states.

The entries for 1979 through 2001 are based on annual micro-data supplied by the IRS Statistics of Income Division. The entries for 1977, 1978 and 2002 on are based on our extrapolations from the nearest available micro data. These tables start in 1977 because that is the earliest year for which we have tax calculators.

• Table 1. In HTML format.
• Table 1. Same but just ASCII text.
• Table 2. Sum of federal and state average marginal rates.
• Table 2. Same but just ASCII text.

Using the 1995 national distribution across years and states.

• Table 3. In HTML format.
• Table 3. Same but just ASCII text.
• Table 4. Sum of federal and state average margianl rates.
• Table 4. Same but just ASCII text.
• Table 6. Same but taxpayers with property tax deduction only.

Using the 1995 distribution of income across states

• Table 7 State average marginal rates.
• Table 8 Sum of state and federal marginal rates.

The table columns are:

1. State ID
2. Year
3. Wages
4. Interest Received
5. Dividends Received
6. Long Term Capital Gains
7. Mortgage Interest Paid (subsidies shown as negative tax)
8. Pension income
9. State Name

The format of the ASCII tables is intended to make it easy for computer programs to read the rather large tables. The state name is left for last in case your software has trouble with embedded blanks. Here is a sample SAS program to read the data (assuming you right click on a table link above and save as ``avrate.txt''.