The US Central Intelligence Agency (CIA) reports that in 2001 Brunei Darussalam's gross domestic product (GDP) was estimated at $6.2 billion. The per capita GDP was estimated at $18,000. The annual growth rate of GDP was estimated at 3%. The average inflation rate in 1999 was 1%. The CIA defines GDP as the value of all final goods and services produced within a nation in a given year and computed on the basis of purchasing power parity (PPP) rather than value as measured on the basis of the rate of exchange. It was estimated that agriculture accounted for 5% of GDP, industry 45%, and services 50%. Foreign aid receipts amounted to about $1 per capita.