The asset purchase programme (APP) was adopted at the beginning of 2015. It is sometimes also referred to as the expanded asset purchase programme (EAPP). The APP is also referred to as "quantitative easing". This is taken to mean the purchase of debt securities by the central bank for monetary policy purposes with the aim of exerting downward pressure on the level of market interest rates. The APP initially consisted of three components: the covered bond purchase programme (CBPP 3; launched in October 2014), the asset-backed securities purchase programme (ABSPP; launched in November 2014) and the public sector asset purchase programme (PSPP; launched in March 2015). The corporate sector purchase programme (CSPP) was added as a further component in June 2016. Under the APP, the Eurosystem has purchased around €60 billion worth of securities every month from March 2015; from April 2016 to March 2017, the monthly purchasing volume totalled €80 billion, afterwards again around €60 billion. From January 2018 to September 2018 the monthly purchasing volume totalled €30 billion, from October to December 2018 only €15 billion. Afterwards the programme was terminated. The Governing Council intends to continue reinvesting, in full, the principal payments from maturing securities purchased under the APP for an extended period of time past the date when it starts raising the key ECB interest rates, and in any case for as long as necessary.