The line graph compares ratio of the elderly over ten decades from 1940 to 2040 in Japan, Sweden and the United States. It is clear that the number of population aged 65 and over increased similarly in USA and Sweden. Meanwhile, the proportion of this group in Japan will be rapidly booming next few decades. In 1940, there were only less than 10 percent of population in three countries were the elderly. While these ratio increased modestly to around 15 percent in USA and Sweden, the number of population aged and over 65 in Japan was in a plunge until the 1990s. The United States had the oldest population until 1995 when Sweden overtook this place.From 1980 to 2030, the ratio of the elderly in the US is relatively stable at 15 percent. At the same time, Japan and Sweden are shown that the extension with 10 percent and 20 percent of population over 65 years old, respectively. At the end of the period, older population ratio in Japan will rocket to 27 percent and be the country which have the most elderly.