Foreign exchange intervention is the buying and selling of foreign currencies by central banks and finance ministries to influence the value of their own currencies. It has become rare for developed countries to intervene in foreign exchange markets. The last U.S. intervention in the foreign exchange market was in March 2011, as part of the G3 intervention with Japan and the European Central Bank (Neely, 2011).
In the bad old days, it was very difficult for researchers to obtain data on foreign exchange intervention, which central banks and finance ministries often treated as confidential. Beginning in the 1990s, however, central banks began to release foreign exchange intervention data to researchers. As intervention became rarer among developed economies, the trend toward releasing intervention data accelerated. Still, researchers needed to contact central banks directly to ask for such data.
About 10 years ago the Federal Reserve Bank of St. Louis began contacting central banks and finance ministries to obtain intervention data to post publicly on FRED to facilitate research on foreign exchange intervention. This dataset has been a little-known feature of FRED, but has been very useful to researchers. The countries that have contributed data include Australia, Germany, Japan, Italy, Mexico, Switzerland, Turkey, and the United States.
How this graph was created: Search for “foreign exchange intervention” and choose the series you want to graph. Note that currencies differ. Here, we chose the ones related to the Japanese yen.
Suggested by Christopher Neely