The IRS receives copies of all W-2s and 1099s that taxpayers get. But it will have questions if you claim less. Not claiming the wages you earned at a company that went out of business and did not send you a W-2 form. The IRS can send you a blank substitute W-2 to use with your own figures. Not knowing if your unemployment funds are taxable.
Unemployment compensation is taxable.
Overpaying your Social Security deductible if you had more than one job in a year. If you worked for two or more employers during 2000, you may have had too much Social Security tax withheld. Not knowing if your dividends are a return of capital and therefore not fully taxable. A return of capital is a return of your original investment and not taxable until and unless the return exceeds your investment. Incorrectly claiming for spousal support.