The given bar chart illustrates the percentage of the total US population aged 65 and over between 1900 and 2000. Overall, the population aged 65-74 remained the dominant group throughout the period. It is also noticeable that all age groups experienced a steady increase over the decades.
At first, the group aged 65-74 in the US started the period at 2.9% in 1900. In the next five decades, the percentage of this group increased steadily, with the largest rise occurring in 1940, when it was about 1% higher than the previous decade. It remained stable for 20 years before continuing to rise and reaching a peak of 7.3% in 1990. After that, it declined to 6.5% at the end of the period.
Secondly, the group aged 75-84 accounted for only about 1% in 1900. It increased very slightly over the next 30 years, by only 0.1% every decade. In 1940, it reached 1.7%, rising by about 0.4% compared to the previous decade. The figure then went up to 2.2% in 1950 and continued to increase more rapidly in the following years, finally peaking at 4.4% in 2000. Meanwhile, the population aged 85 and over started at 0.2% in 1900 and increased gradually. It reached a milestone of 1% in 1980 and peaked at 1.5% at the end of the period.