Can the Central Bank Stop the Rise of the U.S. Dollar with Foreign Reserves?

Brazil's international reserves help mitigate volatility spikes, but they cannot stop a continuous upward trend in the U.S. dollar. According to a discussion published by Seu Dinheiro, spending the foreign currency accumulated by the Central Bank diminishes the shield against external liquidity crises while bringing significant operational and fiscal costs to the public coffers.

Can the Central Bank Use International Reserves to Curb the Rise of the Dollar?

It can, but intervention serves to correct isolated market dysfunctions, not to peg the U.S. currency to a desired level. The analysis presented by Seu Dinheiro highlights that the Central Bank has instruments to inject dollars into the economy; however, the unbridled use of these foreign currencies reduces hard-currency cash availability and exposes the country's vulnerability to new global shocks.

The country's foreign exchange reserves were built over decades through the continuous purchase of dollars that entered the local market via exports and investments. This stock functions as an insurance policy: it ensures that Brazil can honor international commitments, pay for essential imports during periods of scarcity, and mitigate the mistrust of foreign creditors.

When the monetary authority decides to sell spot dollars from its stock, it removes reais from circulation and delivers foreign currency to the spot market. However, if the factors driving the strengthening of the U.S. currency are structural—such as high interest rates in the United States or domestic fiscal uncertainties—the market absorbs the offered dollars without halting the real's depreciation trend.

How Does the Central Bank Operate in the Foreign Exchange Market Without Burning Through Its Stock?

To avoid the direct bleeding of physical reserves, the Central Bank relies primarily on derivative instruments and repo operations. Seu Dinheiro's reporting points out that the debate over foreign exchange operations involves balancing the supply of hedging to the economy without squandering the real assets held within the institution.

The instrument most frequently used by the monetary authority is the traditional FX swap. In these operations, the BC does not deliver physical bills: it assumes the dollar return plus an FX coupon and receives the domestic interest rate variation in exchange. In practice, the institution offers currency protection for companies and funds without removing a single cent from international reserves.

This mechanism, however, is not risk-free. If the dollar rises by more than the Selic rate over the contract period, the Central Bank registers a financial loss on the operation, passing the bill on to the National Treasury. Carrying assets and liabilities on the public balance sheet requires extreme caution, especially at a time when Brazil's gross debt is reaching elevated levels relative to GDP, increasing investor sensitivity to fiscal risk.

Why Does the Dollar Keep Rising Even When the Government Intervenes?

A currency's value reflects the relative perception of risk and return among economies. As Seu Dinheiro noted, the exchange rate is influenced by the flow of dollars entering and leaving the country. If the balance between inflows and outflows is negative, the mere presence of the Central Bank in the FX market only slows down the speed of the movement, failing to reverse the direction of the curve.

Two main drivers determine the trajectory of the exchange rate in Brazil:

• International Financial Conditions: Monetary policy decisions made by the Federal Reserve in the United States attract capital to U.S. Treasuries when interest rates rise there, devaluing emerging market currencies.
• Domestic Fundamentals: Uncertainties regarding compliance with fiscal targets, inflation outside the center of the target band, or the deterioration of public accounts drive away foreign investors and encourage capital flight.

During periods when direct and portfolio foreign investment inflows cool down, the market adjusts the currency price upward. Trying to contain this adjustment through reserve sales is equivalent to trying to dam a tide: the BC spends valuable ammunition while the market absorbs the offerings and continues pricing in real macroeconomic risk.

Additionally, reports from major global analytical institutions frequently reassess the country's attractiveness. When international firms downgrade their recommendations for Brazilian assets, the selling pressure on local stocks and bonds intensifies, demanding more dollar buyers and pushing exchange rates above levels anticipated by domestic agents.

What Should Retail Investors Do with Their Portfolios?

Individual investors should not make financial decisions expecting the Central Bank to artificially drive down the dollar by burning through reserves. Recent economic history demonstrates that heavy currency interventions rarely change the long-term direction of currencies.

For those seeking real-time tracking of exchange rates and valuation metrics, consulting the today's dollar and its fair value dashboard helps identify whether the current rate reflects exaggerated risk premiums or fundamental adjustments in the economy.

Instead of trying to anticipate every auction promoted by the monetary authority, the most prudent approach for those allocating resources in the domestic market involves measuring the impact of foreign currency on the costs of portfolio companies and on the broader inflation of the economy, rebalancing exposure to fixed income and equities with discipline.