Military expenditure in local currency at current prices is presented according to the financial year of each country. Figures in constant (2014) US$ and as a share of GDP are present according to calendar year, calculated on the assumption that, where financial years do not correspond to calendar years, spending is distributed evenly through the year. SIPRI military expenditure data is based on open sources only, including a SIPRI questionnaire which is sent out annually to all countries included in the database. The collected data is processed to achieve consistent time series which are, as far as possible, in accordance with the SIPRI definition of military expenditure, detailed in the sources and methods.
Source: SIPRI Military Expenditure Database, 1988-2015 | Stockholm International Peace Research Institute