A crucial corner of the bond market is signaling that dealers are having an easier time financing their Treasuries holdings, reducing concern that liquidity has become strained in trading of some U.S. government debt.

In the $1.6 trillion tri-party repurchase-agreement market, where dealers turn for short-term funding and investors park cash, Treasuries served as collateral for almost half of transactions in July. That’s the largest share since the Federal Reserve Bank of New York began compiling the data in 2010.

The increase is partly a result of a regulatory change set to take effect in the money-market fund industry, which is boosting demand for Treasuries-backed repos. The growth in such deals is significant because it hints at a revival in the repo business that may grease the wheels of trading in the $13.4 trillion Treasuries market. Liquidity in Treasuries — the ability to trade without substantially moving prices — has drawn scrutiny since the events of Oct. 15, 2014, when the government-debt market convulsed with no apparent trigger.

“This supports liquidity in a broader sense in the cash market, because if you can’t borrow against a security it is not very liquid,” said Joseph Abate, a money-market strategist in New York at Barclays Plc, one of the Fed’s 23 primary dealers. “The trend shows the market is adapting and finding ways to accommodate the demand for repo” even in light of added regulations.

Jury’s Out

The jury is still out on the cause of the October 2014 volatility, and the Treasury Department is conducting its most exhaustive review of the market’s structure in decades. Yet dealers say new regulatory requirements have crimped their ability to take on risk and make markets.

The repo industry has shrunk about 40 percent since peaking in 2008 at around $2.8 trillion. The Fed and other regulators sought to reduce banks’ reliance on this source of funding, because the loss of access to the repo market was seen as contributing to the demise of Lehman Brothers Holdings Inc.

Policy makers are still pushing to wring out risk in the financial system, including through U.S. Securities and Exchange Commission measures that take effect in October and have led billions of dollars to shift into money-market funds that buy only government debt.

Money-Market Trigger