In 2006 exports of crude oil totaled , or about 62.5 percent of the country's crude oil production. The direction of crude oil exports changed after the Revolution because of the U.S. trade embargo on Iran and the marketing strategy of the NIOC. Initially, Iran's post-revolutionary crude oil export policy was based on foreign currency requirements and the need for long-term preservation of the natural resource. In addition, the government expanded oil trade with other developing countries. While the shares of Europe, Japan, and the United States declined from an average of 87 percent of oil exports before the Revolution to 52 percent in the early 2000s, the share of exports to East Asia (excluding Japan) increased significantly. In addition to crude oil exports, Iran exports oil products. In 2006 it exported of oil products, or about 21 percent of its total oil product output. Iran plans to invest a total of $500 billion in the oil sector before 2025.