activity. The mismatch between the job skills of Saudi graduates and the needs of the private job market at all levels remains the principal obstacle to economic diversification and development; about 4.6 million non-Saudis are employed in the economy. Saudi Arabia first began to diversify its economy to reduce dependency on oil in the 1970s as part of its first five-year development plan. Basic petrochemical industries using petroleum byproducts as feedstock were developed. The fishing villages of al-Jubail on the Persian Gulf and Yanbu on the Red Sea were developed. However, their effect on Saudi Arabia's economic fortunes has been small. Saudi Arabia's first two development plans, covering the 1970s, emphasized infrastructure. The results were impressive—the total length of paved highways tripled, power generation increased by a multiple of 28, and the capacity of the seaports grew tenfold. For the third plan (1980–85), the emphasis changed. Spending on infrastructure declined, but it rose markedly on education, health, and social services. The share for diversifying and expanding productive sectors of the economy (primary industry) did not rise as planned, but the two industrial cities of Jubail and Yanbu—were built around the use of the country's oil and gas to produce steel, petrochemicals, fertilizer, and refined oil products—were largely completed. In the fourth plan (1985–90), the country's basic infrastructure was viewed as largely complete, but education and training remained areas of concern. Private enterprise was encouraged, and foreign investment in the form of joint ventures with Saudi public and private companies was welcomed. The private sector became more important, rising to 70% of non-oil GDP by 1987. While still concentrated in trade and commerce, private investment increased in industry, agriculture, banking, and construction companies. These private investments were supported by generous government financing and incentive programs. The objective was for the private sector to have 70% to 90% ownership in most joint venture enterprises. The fifth plan (1990–95) emphasized consolidation of the country's defences; improved and more efficient government social services; regional development; and, most importantly, creating greater private-sector employment opportunities for Saudis by reducing the number of foreign workers. The sixth plan (1996–2000) focused on lowering the cost of government services without cutting them and sought to expand educational training programs. The plan called for reducing the kingdom's dependence on the petroleum sector by diversifying economic activity, particularly in the private sector, with special emphasis on industry and agriculture. It also