US long rates rose for decades into 1981 and then fell for decades into 2020. This page sketches that as a stylised mountain: a trough zone, roughly 40 years of rising rates to a peak zone, then roughly 40 years of falling rates back to a trough zone. The focus is the US 10-year Treasury because the US dollar has been the reserve currency for a long time, so its long rate is the reference point here.
Treat it as an observation and study sketch, not a new named law, a valuation model or a signal. Future markers are theoretical and show regime direction only — there is no yield target for any future date.
Secular regime diagram
≈ 40y up · 40y down · sketch · NFA
Trough regime
Rising-rate regime
Peak regime
Falling-rate regime
Trough → rising (green)Peak zone (centre)Falling → trough (red)
Trough regime
~1940 zone · ~2020 zone
Long rates bottom out across a broad zone rather than on a single day. The sketch marks Jan-dated trough zones at 1940 and 2020; the actual low on FRED DGS10 printed in Aug 2020. The 2020 zone is where the current lap starts on the chart.
Rising-rate regime
~40 years up · 1940s → 1981
From the 1940s into 1981, US long rates rose for decades — an era driven by inflation. Since 2020, yields have sat in a higher range, but that is not yet a proven 40-year uptrend. The Live marker sits early on this slope as a calendar position only, not a call on yields.
Peak regime
~1980 zone · ~2060* theoretical
The 1980 zone captures the secular high; the actual DGS10 high printed in Sep 1981. The ~2060 peak-zone marker is a theoretical sketch from the observed ~40-year half-swings — regime direction only, with no yield print and no target attached.
Falling-rate regime
~40 years down · 1981 → 2020
From 1981 to 2020, long rates fell for decades as disinflation, QE and demographics pulled yields lower. The ~2060 → ~2100 descent on the chart simply mirrors that observed half-swing; it is a sketch, not a forecast.
Attribution & sources
This page does not introduce a new named theory. It sketches an observation — US long rates rose for decades into 1981 and fell for decades into 2020 — and sits alongside related long-horizon frameworks: Kondratiev long waves (~45–60 years), Sidney Homer & Richard Sylla's A History of Interest Rates, and Ray Dalio's long-term debt cycle (~75–100 years). Those frameworks use different clocks; they are cited for context, not combined into one cycle.
Series: US 10-year Treasury constant-maturity yield, FRED DGS10 / Federal Reserve H.15. The only yield figures on this page are the two historical prints in the hover cards (Sep 1981 high, Aug 2020 low). US-only by design — no global averages. Educational study aid only · not financial advice.
Educational content only · not financial advice (NFA) · no yield targets or forecasts · @Dirindin533 / Adirindin Finance. Past patterns do not guarantee future results.
