Us Treasury Par Yield Curve API
US Treasury par yield curve API - every constant-maturity rate from 1 month to 30 years for any published business day, plus the spreads nobody wants to compute themselves. 2s10s, 3m10y and 5s30s are returned with an explicit inversion flag, because the real question is whether the curve is inverted, not what fourteen numbers are. A tenor Treasury did not publish that day is null, never zero. For macro, rates, credit and risk agents.
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Reliability
Daily probe success ratio, last 30 days. Last probed 2026-08-26.
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