Crawling Peg

A crawling peg is an exchange rate arrangement in which a country pegs its currency to an anchor, such as the US dollar or a basket of currencies, but moves the peg in small, regular steps. The adjustments may follow a pre-announced rate, for example 1% a month, or react to indicators such as the gap between domestic and foreign inflation. Central banks use it to avoid both the rigidity of a fixed exchange rate and the swings of a floating exchange rate.

The IMF's annual report on exchange arrangements lists the crawling peg as one of its "soft peg" categories, alongside conventional pegs, stabilized arrangements and pegged rates within horizontal bands. A related category, the crawl-like arrangement, covers currencies that follow a trend in practice without a formal commitment. A crawling band combines the two ideas: the currency floats within an exchange-rate band whose edges themselves crawl.

Picture a ramp instead of a step. A one-off devaluation is like jumping down a large step: sudden, painful and easy to spot coming, so people rush to get out before it happens. A crawling peg turns that step into a gentle ramp. The currency slides a little every week or month, so nobody is surprised and there is less reason to panic.

Countries with high inflation often use the ramp to stop their currency becoming too expensive. If prices at home rise faster than abroad and the exchange rate never moves, local goods slowly become uncompetitive. Letting the currency slip by about the inflation gap keeps the real value roughly steady.

With a constant pre-announced crawl, the central parity after a number of periods is:

• $S_t$ is the official rate (local currency per unit of the anchor) after $t$ periods.
• $S_0$ is the starting rate.
• $c$ is the crawl per period, written as a decimal.
• $t$ is the number of periods, for example months.

Worked example: a currency starts at 100 per US dollar and the central bank announces a crawl of 2% a month. After 12 months the rate is $100 \times 1.02^{12} \approx 126.8$. The currency has lost about 21% of its dollar value, which is close to what it would need if domestic inflation ran about 27 percentage points above US inflation for the year. If the crawl is set below the inflation gap, the real effective exchange rate rises and competitiveness erodes.

Two designs are common:

• Backward-looking crawls. The rate is adjusted to match past inflation differentials, which protects competitiveness but can lock in inflation, because each price rise is passed into the exchange rate and back into prices.
• Forward-looking crawls. The rate is set to a pre-announced path based on target inflation. This can help bring inflation down, but if inflation stays high the currency becomes overvalued.

Latin American countries such as Brazil, Chile and Colombia used crawling pegs from the 1960s to the 1990s to live with persistently high inflation. Chile's crawling band, one of the best known, was dropped in favour of a float in 1999. The economist John Williamson promoted a "basket, band and crawl" (BBC) regime for emerging markets.

A recent case is Argentina. After a large devaluation in December 2023, the central bank let the official peso rate crawl by 2% a month, cutting the pace to 1% a month from February 2025. In April 2025 it replaced the crawl with a managed float inside a widening band; from January 2026 the band's limits have been adjusted using the previous month's inflation figure. Botswana manages the pula against a basket of the South African rand and the SDR with a small annual crawl. Other economies have used crawl-like arrangements in practice, which the IMF classifies from observed behaviour rather than official announcements.

• Speculative pressure. A known crawl invites the carry trade: if local interest rates exceed the crawl plus foreign rates, investors borrow abroad and hold local assets, which can reverse suddenly.
• Inflation inertia. Indexing the exchange rate to past inflation can make inflation self-perpetuating, much like a wage-price spiral.
• Credibility. A crawling peg still requires foreign exchange reserves to defend. If markets doubt the path, a parallel market can open, creating a dual exchange rate.
• Policy constraints. Like any peg, it limits monetary independence under the impossible trinity unless capital controls are in place.

Supporters reply that, for countries leaving very high inflation, a crawl gives a visible anchor for expectations while avoiding the shock of a sudden currency crisis. Most economists see it as a transitional regime rather than a permanent one, often a step towards a crawling band and eventually a float with inflation targeting.

• Bank of Botswana
• Banco Central de la República Argentina