{
  "title": "Optimal FX Interventions with Limited Reserves",
  "publication": "IMF Working Papers, December 12, 2025",
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  "summary": "We investigate the optimal time-consistent use of foreign exchange interventions (FXI) in a small open economy model driven by endowment and portfolio flow shocks, with endogenous FX market depth and a lower bound constraint on FX reserves.",
  "sections": [
    {
      "heading": "Research question and framework",
      "content": "- Investigates the optimal time-consistent use of foreign exchange interventions (FXI) in a small open economy model.\n- Model drivers: endowment shocks and portfolio flow shocks.\n- Key model features:\n  - Endogenous FX market depth.\n  - A lower bound constraint on FX reserves.\n  - Competitive equilibrium environment."
    },
    {
      "heading": "Core findings",
      "content": "- Large capital flows:\n  - Increase conditional exchange rate volatility.\n  - Make FX markets more shallow.\n- Central bank optimal interventions in the constrained environment differ from the unconstrained case:\n  - Not solely targeted at offsetting inefficient fluctuations in the UIP premium.\n  - Incorporate a forward-looking element due to the risk of depleting reserves.\n- Policy characteristics:\n  - Optimal time-consistent FXI policy is state-dependent.\n  - FX sales are more effective than FX purchases.\n  - The policy response to capital outflows may be less than one-for-one or more than one-for-one depending on:\n    - The size of capital outflows.\n    - The economy's net foreign asset position."
    },
    {
      "heading": "Policy implications and comparisons",
      "content": "- Adopting the optimal state-dependent time-consistent FXI policy:\n  - Delivers sizable welfare gains.\n  - These gains significantly exceed those from a simple rule directed at stabilizing current capital flows.\n  - However, the welfare gains materialize only if the initial level of FX reserves is sufficiently far from its effective lower bound."
    },
    {
      "heading": "Subject classifications and keywords",
      "content": "- Subject: Currencies, Currency markets, Exchange rates, Financial markets, Financial services, Foreign exchange, Interest rate parity, Money\n- Keywords: capital flow, Capital Flows, Currencies, Currency markets, Exchange rates, FX intervention, FX Interventions, FX purchase, FX sale, Global, IMF working papers, Interest rate parity, Lower Bound on FX Reserves, Time-Consistent Policy\n\nIMF Working Paper No. 2025/261 — \"Optimal FX Interventions with Limited Reserves\" by Marcin Kolasa, Oliver Vogt, and Pawel Zabczyk (December 12, 2025).\n\n---\n\n Content in this bundle\n\n- Working Paper\n  - Working Paper (Markdown version){rel=\"alternate\" type=\"text/markdown\"}\n  - Working Paper (PDF){rel=\"external\" type=\"application/pdf\"}\n\n---\n\nSource: https://www.imf.org/en/publications/wp/issues/2025/12/12/optimal-fx-interventions-with-limited-reserves-572513"
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    "Authors: Marcin Kolasa, Oliver Vogt, Pawel Zabczyk",
    "Published: December 12, 2025",
    "Series: IMF Working Papers",
    "DOI: https://doi.org/10.5089/9798229033787.001",
    "Investigates the optimal time-consistent use of foreign exchange interventions (FXI) in a small open economy model.",
    "Model drivers: endowment shocks and portfolio flow shocks.",
    "Key model features:",
    "Large capital flows:",
    "Central bank optimal interventions in the constrained environment differ from the unconstrained case:",
    "Policy characteristics:",
    "Adopting the optimal state-dependent time-consistent FXI policy:",
    "Subject: Currencies, Currency markets, Exchange rates, Financial markets, Financial services, Foreign exchange, Interest rate parity, Money",
    "Keywords: capital flow, Capital Flows, Currencies, Currency markets, Exchange rates, FX intervention, FX Interventions, FX purchase, FX sale, Global, IMF working papers, Interest rate parity, Lower Bound on FX Reserves, Time-Consistent Policy",
    "**Working Paper**"
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