The bar chart illustrates the proportion of Australian women across different age groups who gave first childbirth over four decades between 1966 and 2006.
Overall, a gradual decline was observed in the percentage of 19-24-year-old women having their first child, while the figure for those aged from 30 to over 40 generally increased throughout the period. Additionally, women over 40 consistently remained the least first-time childbirth group.
Regarding the age brackets under 30, a large majority of women having their first child in the early 20s was 62% in 1966, nearly more than doubling the figure of those under 19 and in the late 20s, at 35% and 44%, respectively. However, the proportion of women becoming first-time mothers under 19 and those aged from 20 to 24 significantly decreased, dropping at 20% and nearly 40% after two decades, respectively; whereas, the figure for those in late 20s showed an upward trend, peaking at 50% by 1986. Meanwhile, in 2006, all these age groups experienced a stable plunge, with figures being 20% to women under 19, 30% to 20-to-24-year-old women, and 49% to those in their late 20s.
Moving on to over 30, there was a slight rise in the share of women in the 30-to-40 age group giving the first childbirth, from 12% in 1966 to 18% in 1986, after which it experienced nearly three-fold increase after twenty years later, reaching 49% in 2006, making its the highest group in that year. Similarly, the percentage of women aged from 35 to 39 steadily climbed from 9% in 1966 and 29% in 2006, while the figure for those over 40 was negligible, ranging from 1% to 3% over the period.