2019 September Repo Market Crisis

The September 2019 repo crisis was a warning shot that went largely unheeded before COVID. The repurchase agreement market, where banks and dealers borrow overnight against Treasury collateral, normally trades within 5 basis points of the fed funds rate. Rates are stable because the Fed has operated a "floor system" since 2008, paying interest on reserves (IOER) to anchor rates at the target level. On Monday September 16 and Tuesday September 17, 2019, repo rates spiked dramatically. The overnight GC repo rate jumped from 2.29% to 10% intraday on the 17th. Effective fed funds traded above the Fed's 2.25% upper target. The causes were mechanical: corporate tax payments had drained $100+ billion in reserves, Treasury auctions were settling (requiring dealer funding), and post-2008 regulatory requirements had concentrated liquidity in the largest banks, creating bottlenecks in interbank lending. The Fed's response was swift. On September 17, the Fed conducted $53 billion in overnight repo operations, its first open market operations since 2008. Operations grew to $75 billion daily, then expanded to 14-day operations and eventually term funding of hundreds of billions. The Fed began purchasing Treasury bills at $60 billion per month in October 2019, which the Fed insisted was not QE despite the balance sheet expanding by $500 billion over six months. The structural insight was that the post-2008 regulatory regime had created dependencies on the Fed's permanent presence in funding markets. Required reserves plus the liquidity coverage ratio meant banks needed to hold hundreds of billions in excess reserves rather than lend them in repo. The 2017-2019 quantitative tightening had reduced reserves faster than demand could adjust. By late 2019, reserves were too scarce relative to regulatory requirements, creating chronic funding pressure. The lesson was reinforced during COVID. The same dealer balance sheet capacity constraints that caused the September 2019 spike recurred violently in March 2020. The Fed responded with unlimited repo operations and unlimited QE. The Standing Repo Facility (SRF) was created in 2021 to provide a permanent backstop. The episode was a preview of how modern money markets function only with continuous Fed accommodation, an understanding that reshaped both operational policy and the intellectual framework for balance sheet decisions.