; (2) to coordinate with utility or State managed financing programs; (3) to assist in implementation of the applicable State program, including installation of home energy efficiency retrofits; and (4) to coordinate with existing quality assurance programs. (g) Administration and oversight (1) Review of approved modeling software The Secretary shall, on an annual basis, list and review all modeling software approved for use in determining and documenting the reductions in home energy use for purposes of modeled performance rebates under subsection (d). In approving such modeling software each year, the Secretary shall ensure that modeling software approved for a year will result in modeling of energy efficiency gains for any type of home energy efficiency retrofit that is at least as substantial as the modeling of energy efficiency gains for such type of home energy efficiency retrofit using the modeling software approved for the previous year. (2) Oversight If the Secretary determines that a State is not implementing a State program that was approved pursuant to subsection (b) and that meets the minimum criteria under subsection (c), the Secretary may, after providing the State a period of at least 90 days to meet such criteria, withhold grant funds under this section from the State. 204. Special provisions for moderate income households (a) Certifications The Secretary shall establish procedures for certifying that the household of a homeowner is moderate income for purposes of this section. (b) Percentages Subject to subsection (c), for households of homeowners that are certified pursuant to the procedures established under subsection (a) as moderate income the— (1) amount of a partial system rebate under section 202 shall not exceed 60 percent of the applicable purchase and installation costs described in section 202(b)(1); and (2) amount of— (A) a modeled performance rebate under section 203 provided shall be equal to 80 percent of the applicable costs described in section 203(d)(2)(A)