Treasury Auctions and Future Returns

The impact of the bid-to-cover ratio on the U.S. Treasury Market

Hello!

Welcome back to another post. Today, we will be exploring how the success of a treasury auction impacts market returns across Treasuries. In the next post, we will cover the effects on other markets, like U.S. equities and the dollar.

Specifically, we will be looking at a common metric, the bid-to-cover ratio, and its impact. Spoiler: the bid-to-cover ratio has statistically significant effects on future market performance!

This topic has been investigated across various academic papers, and we will showcase a few of the findings from these papers as well. Let’s get into it.

---

Treasury Auctions and Bid-To-Cover Ratio

Before we get into the analysis, I want to explain how Treasury Auctions are conducted and what Bid-to-Cover ratios are.

The U.S. Treasury funds government operations by selling debt securities (Bills, Notes, and Bonds) to the public through a Dutch Auction system. In this format, bidders submit the lowest yield they are willing to accept. The Treasury starts at the lowest yield and works its way up until the entire offering is sold. The highest yield accepted is called the “high yield” or “stop,” and it is the rate that all successful bidders receive.

Primary Dealers (large financial institutions like Goldman Sachs, J.P. Morgan, and Citigroup) are legally obligated to participate in every auction to ensure the debt is sold. Therefore, the real signal comes from the “marginal” demand for these auctions. This demand is driven by investors like foreign central banks, pension funds, and asset managers who choose to bid only when the price is right.

To measure the strength of this demand, we look at the Bid-to-Cover (BTC) Ratio. The BTC ratio is a simple calculation: the total dollar volume of bids received divided by the dollar volume of securities sold.

• A high BTC indicates strong demand. The Treasury had plenty of bidders to choose from, suggesting a high appetite for U.S. debt.

• A low BTC indicates weak demand. This suggests the Treasury struggled to find buyers, forcing it to “dig deep” into the bid book and accept higher yields to fill the offering.

As the data below shows, “normal” demand varies significantly across the yield curve. The 2-year note, for example, is highly liquid and frequently used as a cash proxy, leading to a much higher average BTC (2.82x) compared to the 30-year bond (2.33x).

Because these benchmarks differ, we categorize an auction as “weak” if it falls into the bottom 20th percentile of its specific maturity’s history. These weak points are where we typically see the largest spillover effects into equities and the dollar.

The following charts reflect the historical distributions of the BTC ratio over the last decade (2015 to present).

Now, let’s see the impact that BTC ratios have on Treasuries.

---

The Increasing Importance of the BTC Ratio

There is academic research that backs up the importance of the BTC ratio. Two recent papers explain why this metric is (increasingly) a critical signal.

A 2025 study from Harvard Business School (What Treasury Auctions Reveal About Investor Demand)¹ found that the Treasury market has become significantly more inelastic since 2010.

The market’s price sensitivity to auction results has increased by approximately five times over the last decade. A “weak” auction (low BTC) now triggers a much larger yield spike than it would have historically. The researchers argue that because the market is more brittle, auctions have become the primary venue for investors to gauge global demand.

Research from the European Central Bank (ECB Working Paper No. 2056)² analyzes the specific information contained in the BTC ratio. The authors argue that BTC is a strategic signal from primary dealers regarding the conviction of “informed” investors, such as pension funds and foreign central banks.

The paper highlights two main findings:

• A high BTC leads to lower yields in the secondary market because it reveals that institutional players are aggressive buyers.

• The predictive power of the BTC ratio is strongest during periods of high market volatility.

Together, these papers show that Treasury auctions are important data releases. The HBS paper establishes that the market is increasingly sensitive to these events, while the ECB paper identifies the BTC ratio as the mechanism that transmits demand information to the broader market.