In the 21st century, the world faces a dual demographic problem. First, the world population will continue to grow, increasing from about 6 billion in 2005 to more than 9 billion in 2050. Second, by around that time, the waves of an aging society now enveloping the developed countries as a result of declining birthrates and longer life spans will reach the shores of developing countries. The process is expected to accelerate on a global scale.
The latest U.N. world population estimate makes it clear that humankind is likely to face a situation that it has never experienced before. A major issue for the current century will be how to pool our wisdom in response.
The ratio of elderly people aged 65 or over, which stands at 7.4 percent at present, is forecast to rise to 16.1 percent by 2050. When the elderly ratio exceeds 7 percent, society is said to be aging. When the ratio surpasses 14 percent, it is called an "aged society." In other words, the world has already entered the era of an aging society, and will enter the era of an aged society in 2040, when the elderly ratio is projected to reach 14.3 percent.