79 All scenarios show significant population increases in the developing countries by AD 2030, though Europe's share decreases from its present 14% to about 8% of world population. The projections also show that increased lifeexpectancy will lead to a rapidly-ageing population in developing countries. This will pose severe problems for which their social systems are at present unprepared. These new world population scenarios show that future trends are not inevitable and there are significant opportunities to influence them.