The Harmonised Index of Consumer Prices (HICP) is an indicator of inflation and price stability for the European Central Bank (ECB). It is a consumer price index which is compiled according to a methodology that has been harmonised across EU countries. The euro area HICP is a weighted average of price indices of member states who have adopted the euro. The primary goal of the ECB is to maintain price stability, defined as keeping the year on year increase HICP target on 2% over the medium term.[1] In order to do that, the ECB can control the short-term interest rate through Eonia, the European overnight index average, which affects market expectations. The HICP is also used to assess the convergence criteria on inflation which countries must fulfill in order to adopt the euro. In the United Kingdom, the HICP is called the CPI and is used to set the inflation target of the Bank of England.