The population of country could be divided into three age groups, such as 0-14, 15-59 and more than 60 years old. There are obvious difference between XX and XX for the charts.

It's no doubt that the percentage of age group from 15-59 always higher than other two age groups. Besides, with the increase of aging population, the age group mo than 60 years old also increased. However, the age group from 0-14 decreased sharply from 2000 to 2050. In contrast, the percentage of 15-59 decreased sharply in XX in five decades with the decrease of birth rate, the percentage of sector 0-14 decrease slightly. And the percentage of age group more than 60 increased sharply from 24.1% to 42.3%.

Likewise, the situation  of decrease of birth date in XX happen  in China, the goverment took some measurements to encourage of the couple have more children.