When asked about the QT runoff of Fed balance sheet assets at a presser this past spring, I recall Powell stating that ample bank reserves would be approximately 10% of GDP. Then this quote from Fed Governor Christopher Waller, back in January 2024, said 10% to 11% of GDP would be “an approximate end point for draining reserves out of the system.” So that gives us approximately $2.8 to $3.0T. I would say that the Fed only becomes nervous once we have drained the Reverse Repo facility *and* the bank reserves fall under 12% of GDP, or ~$3.2T.  So, this foots pretty well with your estimate. FWIW.