When Rates Are Not Enough: How Do Unconventional Monetary Policy Tools Work?

The market reaction was immediate. The yield on the 10-year Treasury fell by 5.7 basis points to 4.647%, while the 30-year yield declined by 9 basis points to 5.196%. At the same time, futures on U.S. equity indices rose sharply. Although this is not a monetary policy tool of the Federal Reserve, the situation illustrates very well the principle behind several unconventional central bank interventions. When a new large buyer of bonds enters the market, their price rises and the yield falls. And when the long-term risk-free yield declines, the cost of capital changes across virtually the entire economy.

Under conventional monetary policy, a central bank primarily influences short-term interest rates. Changes in these rates are then gradually transmitted to loans, bonds, currencies and financial asset prices. This mechanism, however, is not automatic.

A household does not take out a 30-year mortgage at the Fed Funds rate, and a company does not issue a 10-year bond directly at the central bank’s policy rate. Between the Fed’s decision and the actual cost of long-term financing stands the bond market, which prices in its own expectations.

The yield on a 10-year government bond can be simplified into the expected path of future short-term interest rates and the term premium, meaning the additional compensation for the risk of holding a long-term bond. Both components are influenced by factors such as inflation expectations, the supply of government debt and fiscal risk. This is precisely why a situation can arise in which the central bank cuts rates while long-term yields nevertheless remain high or even rise.

The current U.S. market is a good example. Pressure on long maturities does not stem solely from expectations regarding monetary policy. Investors are taking into account high budget deficits, a large volume of new Treasury issuance, a growing supply of corporate debt and exceptionally high capital needs of technology companies building AI infrastructure. If the problem originates specifically in this part of the market, changing the short-term rate alone may not be enough.

Treasury Buybacks Are Not QE

Current buybacks of U.S. government bonds must be clearly distinguished from monetary policy. The operation is carried out by the Treasury Department, not the Federal Reserve. The Treasury does not create new central bank reserves and does not pursue an inflation target through buybacks. The primary objective is government debt management and support for market liquidity.

Moreover, this does not represent a net reduction in total U.S. debt. The Treasury buys back part of the existing securities, but the need to finance the budget deficit does not disappear. What changes primarily is the maturity structure and the amount of specific issues available on the secondary market.

The price mechanism, however, is similar to the one used by a central bank when purchasing assets. If the Treasury increases demand for 10- to 30-year bonds, their prices may rise and yields may fall. The market reaction following the buyback announcement demonstrates why direct bond purchases are capable of changing financial conditions even without a move in the policy rate.

QE: Bond Purchases Change the Price of Risk

The best-known unconventional tool is quantitative easing, or Quantitative Easing. Under this policy, the central bank purchases financial assets on a large scale, most commonly government bonds.

The purchase itself is not the only important part. What matters is what happens afterwards.

If the central bank starts buying, for example, 10-year bonds, it increases demand for them and pushes their price higher. The yield falls. At the same time, the investor who sold the bond receives liquidity and must decide where to allocate it next. Part of the capital may move into corporate bonds, equities, real estate or other assets with higher expected returns.

QE therefore does not affect only government bonds. It gradually changes the relative attractiveness of virtually the entire spectrum of financial assets and lowers the cost of financing in the economy.

This mechanism also explains why equities can rise when Treasury yields fall. The risk-free rate forms the basis of the discount rate used to value future corporate cash flows. When it declines, the present value of future earnings rises. Growth companies tend to be the most sensitive because a large share of their expected returns lies far in the future.

Operation Twist: When the Size of the Balance Sheet Matters Less Than Its Maturity Structure

Not every intervention has to mean a further expansion of the central bank’s balance sheet. Operation Twist works primarily with the maturity structure of assets.

The central bank can reduce its holdings of shorter-term bonds while simultaneously purchasing longer maturities. The overall size of the balance sheet does not necessarily change significantly, but demand for individual parts of the yield curve does.

The objective is to push down long-term yields, which are more relevant for mortgages, corporate financing and investment decisions. From this perspective, the current focus of Treasury buybacks on the 10- to 30-year segment of the market is particularly interesting. It shows that the difference between purchasing a two-year and a 30-year bond is not merely a matter of maturity on paper. Each affects a different part of the cost of capital.

Yield Curve Control: When the Yield Itself Becomes the Target

Yield Curve Control goes even further. Under conventional QE, the central bank typically sets the volume of purchases. Under YCC, it proceeds in the opposite way: it sets a yield level or range that it wants to maintain and adjusts the volume of purchases to achieve that target.

The difference is fundamental. If the bank announces that it will not allow a certain yield to be exceeded, the market must account for a practically unlimited potential buyer on the other side.

This is also why investors’ reaction to the current U.S. buyback matters. Mohamed El-Erian pointed out that the planned volumes are small both in absolute terms and relative to the net issuance of new debt. Nevertheless, they may affect market behaviour. An investor aggressively speculating on a further rise in yields suddenly has to price in the risk that the public sector will begin to oppose this move more actively.

The expectation of intervention alone can therefore alter investor positioning even before a larger purchase actually takes place.

Forward Guidance: Sometimes Changing Expectations Is Enough

Unconventional monetary policy does not always have to involve asset purchases. A central bank can also influence the market through the way it communicates the future path of interest rates.

If investors believe that rates will remain low for a longer period, the expected path of future short-term rates changes. This is then reflected in long-term yields as well.

Forward guidance is therefore essentially a matter of managing expectations. The central bank does not have to immediately purchase a single bond. If its communication is credible, the market begins pricing in the new expectations on its own.

In practice, individual unconventional tools often overlap. A central bank may simultaneously purchase assets, communicate the future path of interest rates and provide extraordinary liquidity to the banking system. What matters is not the name of the programme, but the channel through which it seeks to influence financial conditions.

Lower Yields Are Not Automatically Good News

The sharp decline in Treasury yields following the buyback announcement supported equity futures, but the same move may also have a less favourable side.

If long-term yields fall, financing can become cheaper. Mortgages, corporate bonds and loans gradually become more accessible, and financial conditions ease. This is desirable in a recession or during a financial crisis. It becomes far more complicated in an environment where inflation remains a problem.

The Fed can find itself in a situation where it is restraining the economy through short-term rates, while a decline in long-term yields offsets part of that effect. This is precisely what RSM Chief Economist Joe Brusuelas warned about, arguing that efforts to keep yields under control could make it more difficult to return inflation to the 2% target.

Unconventional tools are therefore not a cost-free way to reduce the price of financing. Their effects are transmitted into asset prices, lending activity, currencies and inflation expectations.

The Market Can Be Stabilised, but the Fundamentals Remain

The most important limit of unconventional policy is visible precisely in the current situation.

Higher buybacks can improve bond market liquidity. QE can push yields lower. Operation Twist can change the shape of the curve, and YCC can create an effective ceiling for a particular maturity.

None of these tools, however, reduces the U.S. budget deficit. They do not eliminate the need to issue new government debt and do not reduce the amount of capital that companies borrow in the market to finance data centres and AI infrastructure.

If investors demand a higher yield because the supply of debt or the risk of holding it is increasing, a public institution can dampen that move for a certain period. It cannot, however, remove the reason why it emerged.

That is the essence of unconventional tools. They can very quickly change the cost of capital, liquidity and investor behaviour. Their importance is greatest especially when standard interest-rate policy is unable to influence financial conditions sufficiently, when the transmission mechanism is impaired or when the market faces a shortage of liquidity. If rising yields are driven by a long-term fiscal problem, bond purchases alone will not solve it.