Investment by sector includes household, corporate and general government. For government this typically means investment in R&D, military weapons systems, transport infrastructure and public buildings such as schools and hospitals. Under the 1993 SNA military expenditures on fixed assets were treated as GFCF only if they could be used for civilian purposes of production (e.g., airfields, docks, roads etc.). The 2008 System of National Accounts (SNA) treats all military expenditures on fixed assets as GFCF regardless of the purpose. This indicator is measured as percentage of total gross fixed capital formation. All OECD countries compile their data according to the 2008 System of National Accounts (SNA).