U.S. Treasury / Average interest rates on Treasury securities (monthly)

Monthly average interest rates the Treasury pays on its outstanding debt, by security type (Marketable, Non-marketable) and security (Treasury Bills, Notes, Bonds, TIPS, Floating Rate Notes, Savings bonds ...), in percent (avg_interest_rate_amt), since 2001, newest first. Filter e.g. security_desc:eq:Treasury Bills. Answer: data (rows, all values as strings), meta (count, total-count, total-pages, labels, dataTypes) and links. An unknown field in filter or fields is a clean 400. Source: U.S. Department of the Treasury, Bureau of the Fiscal Service (fiscaldata.treasury.gov), free and without restriction. Free on looot: $0 per call.