Several key factors make Slovenia an attractive location for foreign direct investment (FDI), including: modern infrastructure with access to main EU transportation corridors, a major port on the Adriatic Sea, a highly-educated and professional work force, close proximity to Central/Southeastern European and EU markets, and membership in the EU and Eurozone. However, potential investors in Slovenia have faced challenges including a lack of transparency in economic and commercial decision-making, unclear tender processes, and at times an inconsistent taxation and regulatory structure. EU member states are the biggest investors in Slovenia. Together they account for over 80 percent of all inward investment in Slovenia. The share of inward FDI stock in GDP in 2013 in Slovenia stood at 25 percent. Nevertheless, foreign companies are an important factor to Slovenia's economy. In 2013, they accounted for 19.2 percent of capital, 22.7 percent of assets and 22.1 percent of employees in the entire corporate sector. Their capital and workforce generated 29.4 percent of total net sales revenue and 28.0 percent of total operating profit. Foreign companies accounted for 39.5 percent of exports and 45.2 percent of imports by the Slovenian corporate sector. Sectors of the economy that are most successful in attracting FDI to Slovenia include manufacturing, especially metal products, electrical and optical equipment (in particular production of components for electronic and automotive industry), chemical products and products from plastic materials, paper, pharmaceuticals, rubber, wholesale, retail, and financial and business consultancy. An annual survey of foreign companies in Slovenia, conducted by the Slovenian Public Agency for the Promotion of Entrepreneurship, Innovation, Development, Investment and Tourism (SPIRIT Slovenia), indicates the most decisive factors for choosing Slovenia as a location for investment are the high quality production of export goods, the high skills and expertise of the labor force, prospects for long-term relationships with local customers and suppliers, market access (mostly for services), and geographic position.