"...the market has lost about 2/3s of its ability to convert liquidity to 30-day loans. 90-day is probably similar although there are technical issues with analyzing the chart because 90-day would expire during the end of year crunch so there probably isn't much demand. Next week we'll be able to look at 90-days again.

One of the most critical functions of the banking system is converting short-term deposits into longer-term loans for businesses. Much of the working capital market, for decades has come via money market funds (MM). Joe public or Joe CFO deposits money into a MM. That MM loans it to a bank (usually by buying paper, and usually at a medium duration) and then that bank loans it out to business for inventory, payroll or whatever. The MM has converted Joe's demand deposit into a fixed-duration loan.

The problem we're having is that people are fleeing commercial MM for treasury MM. Those are buying treasuries and thus converting the money to the desirable medium duration BUT that money is loaned to the Fed, and the Fed doesn't make working capital loans. So the deposited money that had been made into working capital has been diverted into the Fed and lost to working capital.

The Fed is kind of trying to address this by loaning out money via various auction/discount windows. BUT, those loans have been overwhelmingly overnight - a particularly nasty demand deposit because it goes back so fast. For a bank to convert that to a 90-day loan it's got to win 90 auctions in a row - a very risky deal with a crunch on. So the Fed undoes the duration conversion, and then some, converting the liquidity into a form that the banks can't make into useful-duration loans.

Right now we have both commercial and treasury MMs. Deposits have shifted from commercial MMs to treasury MMs, and consequently we have less working capital (a commercial MM product) and better credit for the Fed (a treasury MM product).