A German man from Hamburg, who identifies himself only as Yiorgos, carries wood in the village of Skafi some 500 kms north of Athens, September 27, 2011. Skafi once had a population of about 45 families but today it is populated by Yiorgos alone in the winter and about a dozen elderly Greeks who come in the summer. Greece’s population has shrunk by more than 1 percent over the last 10 years, according to a census carried out earlier this year, thereby bucking the trend of the last few decades. The world’s population is projected to reach 7 billion on 31 October, according to official U.N. population projections, presenting what the United Nations Population Fund called both a challenge and an opportunity. (REUTERS/Yannis Behrakis)