Bonds aren’t working as a safe haven like they used to.

On a day when risk aversion swept across everything from stocks and commodities to crypto currencies, Treasuries barely budged. In fact, the S&P 500 and 10-year Treasury futures haven’t been so positively correlated since 1999, with the 60-day metric reaching 0.5 on Wednesday. In contrast, the average correlation over the past two decades was negative 0.3, meaning a decline in stocks was often accompanied by a rally in bonds.

The relationship flip signals that the role of Treasuries as a shock-absorber has been eroded as the fear of inflation becomes a common denominator for both stock and bond investors. If it persists, it would mark a sea change as strategies such as risk-parity and 60/40 are likely to become more volatile.

“Long bonds as your hedge worked in a Goldilocks era” of stable growth and inflation, said Charlie McElligott, a cross-asset strategist at Nomura Securities. “But now, due to the pandemic response, that old dynamic simply no longer applies. Inflation is a volatility catalyst.”

The stock-down-bond-up scenario that investors have grown accustomed to has only been a staple since 2000. Earlier, a positive correlation had been more common as inflation was more volatile.

While the core U.S. consumer price index increased in April at the fastest pace since 1982, the Federal Reserve has insisted the surge is “transitory” and the central bank will be patient in removing monetary stimulus. If the Fed is right, the bond-stock correlation could normalize, said McElligott.

“Only in the case of an extreme inflation overshoot would the Fed’s hands be tied,” forcing it to raise rates more quickly and crash both bonds and stocks, he said.