A Quarter Is Not a Strategy: Reading the 2026Q1 COFER Move

For central banks' official foreign-exchange reserve portfolios, a quarterly currency-share movement is a measurement event before it is a strategy story. The IMF's 2026Q1 release offers a clear test: the reported dollar share rose even as total reserves edged down, and the IMF said exchange-rate valuation accounted for around half of that increase. The task is to trace what market prices, bond values, active management, and reporting changes can each contribute, then keep the conclusion within what a single quarter can support.

The dollar share rose while the reserve stock edged lower

The IMF's July 1, 2026 data brief reports total foreign-exchange reserves of $13.10 trillion in the first quarter of 2026, compared with $13.15 trillion in the fourth quarter of 2025. Over the same interval, the dollar's share rose from 56.42 percent to 57.13 percent. Those two movements can coexist because a share describes composition, while the total describes the size of the pool. A smaller pool can have a larger fraction in dollars if the relative values of the components change or if the composition shifts.

The release identifies the U.S. dollar's mild appreciation against major currencies as a key driver of the increase in its reported share. It says exchange-rate-driven valuation effects accounted for around half of the change. That wording is deliberately limited. It assigns a substantial role to a market valuation mechanism, but it does not say that all of the movement was valuation, nor does it identify every transaction behind the remainder.

The mechanism is easiest to see by treating the reported reserves as a portfolio valued in a common accounting unit. Suppose the dollar value of dollar-denominated assets is stable while the currencies of other reserve assets weaken against the dollar. When those non-dollar assets are translated into the common unit, their reported value can fall relative to the dollar assets. The dollar portion of the measured total then rises even if the reserve manager has not deliberately bought more dollar securities. The observed share has changed because the values used to calculate the share have changed.

The reverse can also occur. If non-dollar currencies appreciate against the dollar, or if dollar-denominated assets lose value relative to the rest of the portfolio, the measured dollar share can fall without a comparable decision to sell dollar assets. The point is not that allocation decisions never matter. It is that the same percentage can be produced by a change in holdings, a change in prices, or both. A quarterly data release records the ending composition; the source of the movement must be separated analytically.

The other currencies in the IMF release reinforce the point. The euro's share declined from 20.38 percent to 20.03 percent, while the renminbi's share edged up from 1.95 percent to 1.99 percent.