Bond Yields and Oil Prices Rattle Global Markets Through a Brutal Week

A Week Markets Would Rather Forget

It was a rough stretch for anyone watching their portfolio. Global stocks closed out the week of August 18–22 under heavy pressure, battered by a relentless rise in government bond yields and oil prices that refused to give investors any breathing room. Global stocks were headed for a mostly lower week as strain in global bond markets showed little sign of abating, and a diplomatic deadlock in the Gulf lifted oil prices to one-month highs. For everyday investors, it was a stark reminder of just how interconnected energy markets, government debt, and stock prices really are.

The S&P 500 tumbled 1.4% on the week, while the Nasdaq lost 2% — both indexes snapping three-week winning streaks. The Dow slid 0.9% for back-to-back weekly losses. The damage wasn't limited to the United States. The downturn also affected stocks beyond the U.S., with the MSCI All Country World Index posting a weekly decline of almost 1%.

The Bond Market at the Heart of It All

The S&P 500 was pressured by a run in sovereign bond yields to multi-year highs amid concerns of persistent inflation and elevated oil prices. Fixed income strategists attributed the run — which began in June — to intensified concerns over a budget deficit set to eclipse its 2025 level, inflation stuck above the Federal Reserve's 2% target, and a surge in corporate debt issuance competing with Treasuries for investor attention.

The numbers were jarring. The yield on the 30-year U.S. Treasury bond climbed back to about 5.25%, while the 10-year yield reached 4.71%. Japan's 10-year bond yield reached its highest level in three decades. These aren't just abstract figures — higher bond yields can have broad consequences for financial markets because they increase borrowing costs for governments and companies while reducing the relative attractiveness of riskier assets such as stocks.

The Treasury Department attempted to intervene. The U.S. Treasury surprised investors on August 19 when it announced it would at least double the amount of longer-dated Treasury bonds it would buy back from investors — from $2 billion to $4 billion per operation — between September 9 and November 4. But the relief was fleeting. U.S. government bond yields resumed their climb after Wednesday's surprise intervention by the Treasury brought barely a day of relief from selling sparked by concerns about elevated inflation and fiscal pressures.

Oil and the Gulf Standoff Add Fuel to the Fire

Oil prices held near their highest levels in weeks, as the deadlocked standoff between the United States and Iran kept supply concerns elevated in the Middle East. Brent crude, the international benchmark, rose to $91.90 a barrel, while U.S. benchmark crude edged to $84.57 a barrel. Prices climbed steadily since the start of August, when Brent was trading at around $87.38 a barrel, as the standoff over the Strait of Hormuz kept supply concerns elevated.

The U.S. Treasury market erased all its gains for the year as the war-driven surge in oil prices set investors panicking about both inflation and growth risks. A Bloomberg gauge of its performance turned negative for the year after losing 1.7% this month — a milestone that came as stagflationary angst sent yields higher and forced Wall Street to reel in its expectations for lower interest rates.

What Comes Next

Analysts were skeptical that Treasury Secretary Bessent could find enough spending cuts to seriously curb a budget deficit of more than 6% of gross domestic product, with interest charges alone this year running at $1.2 trillion, while the U.S. debt pile just crossed $40 trillion. That fiscal backdrop makes a quick resolution to the bond market turbulence seem unlikely.

Not everything was bleak. The financials sector offered a boost to the broader market, with crypto-related stocks seeing sizable gains as Bitcoin posted a weekly advance of 22%. Robinhood shares jumped almost 14%, while Coinbase added 8%. The direction of Treasury yields and oil prices will remain closely watched as investors assess whether inflationary pressures will persist and how central banks respond. With no Federal Reserve meeting on the calendar this month, markets will be left to wrestle with those questions largely on their own — at least for now.