INTEREST RATES

Interest rates are the price of borrowing money — the cost a borrower pays to a lender for the use of capital over time.

The mechanism

Central banks set rates at the short end. The Federal Reserve controls the federal funds rate; market forces determine longer-duration rates, reflecting expectations about future growth, inflation, and risk. When central banks raise rates, borrowing becomes more expensive, slowing consumption and investment, which reduces demand and tends to bring down inflation. When they cut, cheaper borrowing stimulates growth. The core challenge is calibration: monetary policy works with long and variable lags, so real-time adjustment is genuinely hard. Rates affect everything from mortgage costs and credit card rates to the cost of capital for businesses, shaping how firms approach capital allocation, and the baseline "risk-free" return against which every other asset is benchmarked.

The 2022-2024 cycle

The most aggressive rate-hiking cycle in four decades — from near-zero to over 5% in the US — stress-tested assumptions that had been treated as permanent. Technology valuations compressed sharply because high rates disproportionately hit long-duration assets. Commercial real estate repriced as refinancing costs overwhelmed operating cash flows. Regional banks faced duration mismatches between their held-to-maturity bond portfolios and deposit liabilities. Startup funding dried up as venture capital investors raised their return hurdles and growth-at-any-cost models stopped penciling out. The cycle clarified which businesses were structurally profitable versus which had been subsidized by cheap capital.

Duration risk and the yield curve

Duration measures how sensitive an asset's price is to changes in interest rates. Long-duration assets — 30-year bonds, high-growth equities whose earnings are mostly in the distant future — fall more sharply when rates rise than short-duration assets do. The 2022 rate shock was unusually painful for technology investors because the sector had been priced for a zero-rate world, discounting cash flows decades out at near-zero rates. The yield curve adds another layer: when short-term rates exceed long-term rates (an inverted yield curve), bank lending margins compress, credit creation slows, and recession has historically followed within 12 to 18 months. The curve's shape encodes the collective view on where growth and inflation are headed.

Real versus nominal rates

The distinction between nominal rates (the stated rate) and real rates (nominal minus inflation) is often more important than the headline number. A 5% nominal rate with 2% inflation means a 3% real rate — genuinely restrictive. A 5% nominal rate with 5% inflation means a 0% real rate — effectively neutral. The 2022-2023 hiking cycle looked aggressive in nominal terms, but real rates only turned meaningfully positive in late 2023. That delay explains why the economy proved more resilient than most forecasters predicted: tightening was slower in real terms than the headline numbers suggested, and consumers with fixed-rate mortgages were largely insulated from the shock.

Open Questions

• How much of the post-2022 rate environment reflects structural factors (deglobalization, fiscal deficits, aging demographics) versus cyclical ones that will reverse?
• If neutral rates have genuinely shifted higher, what does a permanently more expensive cost of capital mean for equity valuations built on a decade of near-zero rates?
• Can central banks credibly commit to inflation targets when fiscal policy is running persistent deficits — and who wins that tug-of-war?
• What happens to commercial real estate, private credit, and leveraged buyouts if rates stay elevated through the next refinancing wave?

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