Tax Parameters Will Remain Virtually Unchanged for 2010 September 16, 2009 Mark Robyn Mark Robyn 2010 will mark the first time that the federal personal exemption and standard deduction (for most taxpayers) have not increased since the IRS started inflation adjusting these parameters in the mid 1980s. Each year the IRS adjusts a host of tax parameters to account for inflation. Things like the standard deduction, the personal exemption, and the tax brackets (the income levels where each tax rate kicks in) are increased to keep up with the Bureau of Labor Statistic’s (BLS) Consumer Price Index (CPI) measure. These adjustments help taxpayers avoid increases in tax liability that are simply due to inflation. Today the Bureau of Labor Statistics released its August 2009 inflation data. Each tax year’s adjustments are based on the average CPI for the 12-month period ending August 31 of the previous year, meaning that the CPI data that was released today will be used to determine the tax year 2010 tax parameters. Specifically, the IRS uses the All Items CPI for All Urban Consumers (CPI-U). This index has actually fallen from where it was a year ago, indicating deflation rather than inflation. However the 12-month average is still slightly higher than last year’s. But the relatively low CPI numbers mean that for 2010 the tax parameters will see very small adjustments, and in some cases no adjustments at all (the IRS uses a rounding method that results in some parameters receiving no adjustment). I should note that using the term “inflation” here is not entirely accurate. CPI does not measure total inflation, rather it measures “changes in the prices paid by urban consumers for a representative basket of goods and services.” But the general idea is to adjust for actual inflation. You can read about CPI here and inflation here. Today we released a new Fiscal Fact outlining the major inflation adjustments for tax year 2010. From the Fiscal Fact, titled Inflation Adjustment of Tax Brackets Almost Zero for Next Year: The numbers released today indicate that this year will mark the smallest inflation adjustment on record… While last year saw some of the largest year-over-year increases in most inflation-adjusted tax parameters (4.26%), year-over-year inflation for the purposes of this year’s adjustment was less than 0.2 percent… Stay informed on the tax policies impacting you. Subscribe to get insights from our trusted experts delivered straight to your inbox. Subscribe Share Tweet Share Email Topics Center for Federal Tax Policy Individual Income and Payroll Taxes Tax Law