Last Friday we made you a promise about a number. Our weekly count of the dollars the banking system can lend had risen two weeks running, and we said that if Wednesday's reading made it three, we'd revisit the June buying area for bitcoin.

Wednesday's reading fell $94.0 billion, to $5,770.2 billion. The two rises before it had added $95.4 billion, so the count is back within $1.5 billion of where it stood on 2 September.

Bitcoin closed Wednesday at $84,493 and yesterday at $84,319. On 2 September it closed at $77,027. Over those three weeks our count went nowhere and bitcoin rose 9.5%.

That cuts against what we told you on the 18th. We said the supply of dollars, more than the price of them, was what set crypto's floor, and that bitcoin had followed our count up while everyone else was watching the Fed's rate. Three weeks on, the count and the price have gone separate ways.

We build that count ourselves, once a week, from the Fed's own balance-sheet figures, and we have 95 readings of it going back to December 2024. When it rises there are more dollars around to buy things that pay no interest, and when it falls there are fewer. It's the number we lean on when we tell you whether dollars are getting easier or harder to come by, which is why we tied a promise to it.

The condition we set for revisiting the June call didn't happen, and we'll come to what that means for it. The more useful question is what the count was measuring when it rose, and what has been holding bitcoin up if the count wasn't.

If you hold bitcoin at $84,000, it matters who is paying. New dollars entering the system can keep buying for months. People moving savings they already had into bitcoin stop when they run out of savings to move, or change their minds.

Either we misread our own number on the 18th, or bitcoin is standing on a buyer our count can't see, and we'd do different things depending on which.