Represents tax withheld on (a) salaries and wages; (b) certain tip income; (c) pensions and annuities; (d) certain gambling winnings; and (e) distributions from profit-sharing plans, retirement plans, and Individual Retirement Arrangements (IRAs). Also included are taxes withheld as a result of "backup withholding" on certain interest, dividends, and royalty payments, which otherwise were not subject to withholding.
For additional information about the return filing requirements, see the annual reports, Statistics of Income-Individual Income Tax Returns at https://www.irs.gov/uac/soi-tax-stats-historical-data-tables.
U.S. Department of the Treasury. Internal Revenue Service, Individual Income Tax Filing: Tax Payments: Income Tax Withheld [TXPMTITW], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/TXPMTITW, October 15, 2018.