The claim about an event
The yen intervention — and what it did to our own measure
In July 2026 Japan bought yen twice, and on 31 July Washington joined in — the first joint US–Japan intervention in nearly three decades. The yen rallied off a 40-year low to around 155 per dollar. Bitcoin was widely reported alongside it.
This one deserves an admission about our own measure, because it cuts against us. The BIKENZO chart is the balance sheets of the ECB and the Bank of Japan converted into US dollars. A stronger yen therefore RAISES our line mechanically — the Bank of Japan need not create a single yen for the number to go up, because the same yen are simply worth more dollars. When Tokyo and Washington bought yen, part of any rise you see below is exchange rate, not money creation. We say so here rather than let the figure flatter the story, and it is the reason the third row matters more than the second: what the money was doing before the intervention cannot be explained by the intervention.
The window, measured
2026-07-10 to 2026-08-04 · 25 days. From the day before the first intervention on 11 July to the confirmation of joint action and the days after it.
| Bitcoin over the window | $64,114 → $64,056 | −0.1 % |
| The BIKENZO chart over the window | 11.49T → 11.53T | +0.3 % |
| The BIKENZO chart in the 90 days before it | −1.3 % |
The honest answer
In the ninety days before this window the money measure was close to flat (−1.3 %). On this occasion the event has a case: the move was not already under way.
The threshold used above is two per cent over ninety days, stated here so you can hold it against us. News explains a day. It rarely explains a quarter — and the figures above are the whole of the argument, computed from the same sources the public chart draws.
Check it yourself
- Al Jazeera — Japan and US confirm rare joint intervention to prop up yen
- Nikkei Asia — Japan carries out yen-buying intervention as US executes rate check
- CNBC — Japan yen intervention: why the US stepped in
- Investing.com — Japan spent $20.7 billion on intervention on 11 July
Open to everyone, no account. The last 90 days are what a subscription adds.
Stage Strategy GmbH publishes market data. This page reports what a stated window measured; it is not financial advice, not a recommendation, and makes no claim about what any price will do next. Nothing here asserts that any named person or event caused a price move — the question is posed because it is asked, and answered with figures anyone can check.