Net lending is the net amount a unit or a sector has available to finance, directly or indirectly, other units or other sectors. Net lending can be derived as saving plus net receipts of capital transfers minus net purchases of non-financial assets (i.e. the balance of the capital account), or it can be measured as the difference between net acquisition of financial assets and net incurrence of liabilities (i.e. the balance of the financial account). Although it can be derived via either approach it is important to note that, in practice, achieving this equivalence is one of the most difficult tasks in compiling national accounts. Negative net lending is called "net borrowing". This indicator is measured as percentage of gross domestic product (GDP). All OECD countries compile their data according to the 2008 System of National Accounts (SNA).