By asahifile 
Japan’s Ministry of Finance published the daily record of its July–September currency operations on 9 November, and the table is smaller than the story around it. Three days: ¥7,975.6 billion on 30 July, ¥5,552.3 billion on 31 July, ¥1,871.4 billion on 3 August. The ¥15,399.3 billion total is the largest yen-buying campaign in a series dating to 1991, and the first day beat April’s one-day record of ¥6,278.7 billion. On 11 November the yen traded near ¥159, five yen stronger than the four-decade low near 164 that triggered the operation, and where it has sat since mid-August.
Half of it went out on the first morning
Divide the ministry’s own figures and a design appears. The 30 July operation was 51.8 per cent of the campaign, the second day 69.6 per cent of the first, the third 33.7 per cent of the second: a descending ladder, not a schedule. April was as concentrated but shaped the other way — 30 April took 53.5 per cent, the second day fell to 12.4 per cent of the first, then the third jumped to 599 per cent of the second at ¥4,675.9 billion on 6 May. April probed, then reloaded into Golden Week’s thin liquidity; July reloaded once.
The same yen total, two dollar totals
Wires converted ¥15.4 trillion into $96.5 billion on 28 August and into $97.16 billion on 9 November. No yen changed, only the conversion date, and the 0.68 per cent gap matters when the dollar figure becomes the headline. The ratios also say where the money filled: ¥158.37 per dollar on the 30 July leg, ¥158.5–159.6 for the campaign, ¥159.4–160.4 for April.
An unwinding test: at ¥159, the yen bought in July and August would fetch about $96.85 billion if sold back — 0.36 per cent above the $96.5 billion cost figure, 0.32 per cent below the $97.16 billion one. The record campaign sits inside the noise of its own accounting. April, bought at a weaker rate, is up about 0.9 per cent.
Five yen of relief, then three point eight back
The yen ran from about 163.9 to 155.20 by 3 August and was around 159 on 11 November, according to Trading Economics — 3.8 yen given back from the peak within three weeks. Net of the campaign, the record money bought roughly 4.9 yen: about half a yen per $10 billion. Extrapolated — crudely, since a second operation meets a market that has seen the first — a move from 159 to 150 would cost about $178 billion, 1.84 times July–August. A strategist quoted by the Business Times described the working assumption: nobody intends to push dollar-yen materially below 150, so 155 to 165 holds.
It took 102 days to see the table
Tokyo and Washington confirmed the joint operation within days; the monthly release on 28 August gave a total for 30 July to 26 August without dates; the daily breakdown came on 9 November, 102 days after the first trade. April was faster: 29 days to the monthly total, 99 days to the daily table.
Only the daily table showed that the American leg on 31 July sold euros for yen rather than dollars, that it ran three sessions, not the two markets assumed, and that the Bank of Korea ran won-buying on a matching timetable, per Reuters. Even the entry point is contested: 164 in most accounts, 163 in Reuters’ August piece.
When the arithmetic flips
The carry gap has not closed. The Bank of Japan’s rate is 1.25 per cent after September’s increase; it held on 30 October by eight votes to one. The Federal Reserve’s range is 3.75–4.00 per cent, and futures priced an 85 per cent chance of another hike in December by 9 November. That 2.6-point gap is what pays for being short yen.
So the verdict is narrow. If the Fed hikes in December and the Bank of Japan waits until January, a retest of 165 is the base case and another three-day operation buys weeks, not a trend. If the Bank of Japan moves 25 points and the Fed pauses, the pressure releases without a yen of reserves, and July’s ¥15.4 trillion reads as the top of the range rather than its floor. Anyone hedging on Tokyo defending a number should note what 155.20 lasted: five days.
What to watch
- The ministry’s next monthly release, due at the end of November.
- The December Fed and Bank of Japan meetings, in that order.
- Whether dollar-yen closes above 160, the level that preceded both 2026 campaigns.
- Capacity: about $170 billion used, roughly 17 per cent of the $1 trillion war chest.
Sources: Ministry of Finance, July–September 2026 and April–June 2026 intervention operations; Reuters, 9 November 2026; Reuters, 28 August 2026; Business Times; J.P. Morgan; Trading Economics. Conversions, implied rates, day shares and the unwinding arithmetic are this site’s calculations.