; and (6) during fiscal year 2019, none of the funds available under this heading are available for the cost, as defined in section 502 of the Congressional Budget Act of 1974, of commitments to guarantee bonds and notes under section 114A of the Riegle Community Development and Regulatory Improvement Act of 1994 ( 12 U.S.C. 4713a ): Provided , That commitments to guarantee bonds and notes under such section 114A shall not exceed $500,000,000: Provided further , That such section 114A shall remain in effect until December 31, 2019: Provided further , That of the funds awarded under this heading, not less than 10 percent shall be used for awards that support investments that serve populations living in persistent poverty counties: Provided further , That for the purposes of this paragraph and paragraph (1) above, the term persistent poverty counties means any county that has had 20 percent or more of its population living in poverty over the past 30 years, as measured by the 1990 and 2000 decennial censuses and the 2011–2015 5-year data series available from the American Community Survey of the Census Bureau. Internal Revenue Service taxpayer services For necessary expenses of the Internal Revenue Service to provide taxpayer services, including pre-filing assistance and education, filing and account services, taxpayer advocacy services, and other services as authorized by 5 U.S.C. 3109 , at such rates as may be determined by the Commissioner, $2,491,554,000, of which not less than $8,890,000 shall be for the Tax Counseling for the Elderly Program, of which not less than $12,000,000 shall be available for low-income taxpayer clinic grants, and of which not less than $15,000,000, to remain available until September 30, 2020, shall be available for a Community Volunteer Income Tax Assistance matching grants program for tax return preparation assistance