; and (B) the amount of credits allowed under section 36C of the Internal Revenue Code of 1986 with respect to such remittance transfer fees. (2) Timing and estimates Amounts described in paragraph (1) shall be deposited into the Trust Fund by the Secretary of the Treasury at least monthly from the general fund of the Treasury on the basis of estimates made by the Secretary of the Treasury. Proper adjustments shall be made in amounts subsequently transferred to the extent prior estimates were in excess of, or less than, the amounts required to be deposited pursuant to this subsection. (c) Expenditures from Trust Fund Amounts in the Trust Fund may only be used, consistent with appropriation Acts— (1) to employ and train additional U.S. Border Patrol agents; (2) to employ and train officers and support staff employed in enforcement and removal operations of U.S. Immigration and Customs Enforcement; (3) to plan, design, construct, improve, or maintain barriers along the international border between the United States and Mexico; and (4) to plan, design, construct, improve, or maintain detention facilities for aliens residing in the United States without lawful immigration status. . (b) Clerical amendment The chapter analysis for chapter 33 of title 31, United States Code, is amended by inserting at the end the following: 3344. Border Enforcement Trust Fund. .