Tax returns filed with the IRS are subject to examination and adjustment, commonly called an IRS audit. Only a small percentage of returns (about 1% of individual returns in IRS FY 2008) are examined each year. The selection of returns uses a variety of methods based on IRS experiences. On examination, the IRS may request additional information from the taxpayer by mail, in person at IRS local offices, or at the business location of the taxpayer. The taxpayer is entitled to representation by an attorney, Certified Public Accountant (CPA), or enrolled agent, at the expense of the taxpayer, who may make representations to the IRS on behalf of the taxpayer.