The current system of own resources depends on three streams of revenue collected by Member States to finance expenditure: ‘traditional own resources’, consisting of 80 % of customs duties and sugar levies collected by Member States in accordance with the EU’s common external tariffs (€20.1 billion in 2016, or 14 % of revenue – see Figure 2); an own resource made up of a percentage of the Member States’ estimated income from value added tax (VAT) – €15.9 billion in 2016, or 11.1 %; and an own resource based on a fixed percentage of Member States’ GNI (€96.2 billion in 2016, or 66.8 %). There are other sources of revenue that complement own resources: taxes on EU staff salaries, contributions from non-EU countries to certain EU budget programmes, fines on companies for breaching competition law, and interest on late payments and fines. However, own resources account for the lion’s share of EU revenue, amounting to €132.2 billion in 2016, compared with €1.4 billion in other revenue. There is sometimes also surplus revenue carried over from one financial year to the next: in 2016, the surplus carried over from 2015 was €10.6 billion. Own resources mobilised to cover EU budget spending are currently capped at 1.20 % of EU GNI per year.