Collapse of banking system and introduction of capital controls in October 2008, see Deutsche Bundesbank, Monthly Report, July 2010, pp 52-53. Since 2020, only middle rates have been published; see BBEX3.A.ISK.EUR.CA.AC.A04.
Methodology
Until 2007, calculated on the basis of mid-month and month-end rates, from 2008 to 2018 on the basis of daily rates and 2019 on the basis of month-end rates.
