The changes in demographic structure have created a number of social issues , particularly a potential decline in workforce population and increase in the cost of social security benefits such as the public pension plan . A growing number of younger Japanese are not marrying or remain childless . In 2011 , Japan 's population dropped for a fifth year , falling by 204,000 people to 126.24 million people . This was the greatest decline since at least 1947 , when comparable figures were first compiled . This decline was made worse by the March 2011 earthquake and tsunami , which killed nearly 16,000 people
March 2011 earthquake and tsunami
2011 Tōhoku earthquake and tsunami
Japan