The 2018 World Population Data Sheet highlights the global trend of population aging, projecting that the share of older adults (ages 65+) will rise from 9% in 2018 to 16% by 2050, while the share of children (ages 0-14) is expected to decline from 26% to 21%. Different countries face unique demographic challenges related to age structure, affecting policies and resource allocation, particularly regarding education and economic development. The document emphasizes that investments in education are crucial for economic growth, especially in high child dependency countries, while also addressing the growing costs of supporting an aging population.