Some countries have a crawling peg for their nominal exchange rate: they adjust it by a fixed

Question:

Some countries have a “crawling peg" for their nominal they adjust it by a fixed percentage every year. For example, Boversia might reduce its against the dollar by 3 percent per year. Why might a country adopt a crawling peg?
Exchange Rate
The value of one currency for the purpose of conversion to another. Exchange Rate means on any day, for purposes of determining the Dollar Equivalent of any currency other than Dollars, the rate at which such currency may be exchanged into Dollars...