If a sponsor filed a joint tax return with a spouse, but is qualifying using only his/her own individual income, the sponsor must submit evidence of that individual income. This evidence would include, for example, the sponsor’s own W-2(s), Wage and Tax Statement, and if necessary to reach the income requirement, evidence of other income reported to IRS which can be attributed to him/her, usually on Forms 1099.
Also, take this into account when filling out your forms. The sponsor’s total household size is used to determine the correct Federal Poverty Guideline. For purposes of Form I-864, a household size includes the total of the following groups of individuals:
· Sponsor;
· Person(s) the sponsor is sponsoring on the Affidavit of Support (will always be one if the sponsor is using Form I-864EZ instead of Form I-864);
· Sponsor’s spouse, if the sponsor is married;
· All of the sponsor’s children, as defined in section 101(

(1) of the Act, except those that have (1) reached the age of majority (i.e., are at least 18 years old) or are emancipated under the law of the person’s domicile, and (2) are not claimed as dependents on the sponsor’s most recent Federal income tax return;
· Other persons lawfully claimed as dependents on the sponsor’s tax return for the most recent tax year;and
· The number of siblings, parents, and/or adult children who (1) have the same principal residence as the sponsor, and (2) have combined their income with the sponsor’s income by submitting Form I-864A.
Note: When calculating household size, do not count any person more than once.
Also...
Note: Typical proof that a sponsor was not required to file a tax return for a particular year would consist of a written statement from the sponsor, signed under penalty of perjury, attesting to the amount of his or her income for the relevant year and to the fact that a tax return was not required by law. USCIS adjudicators handling Form I-864 issues should be aware of the income threshold for the requirement of filing a tax return for the last several years, so that an RFE for evidence of the law is not neces sary. In particular, the Instruction booklets for each year’s Forms 1040, 1040A, and 1040EZ specify the income threshold below which a person is not required to file a return.
http://www.uscis.gov/propub/template.htm?v...;hash=0-0-0-524Hope that helps...