The current Zambian population growth rate would result in the country\'s population doubling by 2035 and poses a challenge to authorities to put in place policies that will commensurate with the population growth, a government official has said on Monday. Chileshe Kandeta, Public Relations Officer in the Ministry of Finance and National Planning, said in a statement in commemorating this year\'s World Population Day that the country\'s population had expanded at an average rate of 2.8 percent per year between the years 2000 and 2010. \"At a growth rate of 2.8 percent, Zambia\'s population would double or reach 26 million by the year 2035,\" he said. According to the 2010 National Censuses on Population and Housing, the Zambian population was now estimated at 13 million from 9.9 million in 2000. According to the official, the population growth was due to high fertility, declining mortality and other measures the government had implemented to improve the quality of life, adding that the government was taking proactive steps to attain economic growth rate that was commensurate with the population growth in line with its development plans. Meanwhile, the official has said the world population presented both challenges and opportunities for world leaders, decision- makers and policy makers with regard to the provision of social and economic opportunities for a decent livelihood According to the United Nations Development Program (UNDP), the world population would soon reach 7 billion of which 3.7 billion would be aged 24 and below. The theme for this year has since been dubbed \"The World at Seven Billion\". According to the Zambian official, the youthful world population would provide a valuable resource of human capital that should be utilized to foster greater economic and social development.