Dependency is the notional support burden placed on the working-age population by younger (0–14) and older (65+) age groups. Declines in Māori child mortality and consistently high fertility rates from the 19th century to the later 20th century resulted in a large Māori child population over this period. Children made up 50% of the total Māori population in the 1960s, which meant youth dependency ratios were high. Though the birth rate declined from the 1960s, the Māori child population continued to grow, so the youth dependency ratio remained high. The number of older Māori people remains proportionally small in the 21st century, so this dependency ratio is low. However, the older Māori population is projected to grow.