Please help me check my descriptions for the following chart (IELTS writing task 1: Line graph)

The line graph compares three countries, namely Janpan, Sweden and the US in terms of their percentages of people aged 65 or more from 1940 to 2040.

It is clear that there were dramatic increases in the proportion of the ageing population in all three nations over the period shown. While the US and Sweden saw a steady rise in the percentage of elderly citizens over the century, that of Japan changed more wildly.

In 1940, of all three countries, America had the highest percentage of people who are aged 65 or more, at around 9%. The figure for Sweden was a slight lower, starting with about 7%. A considerable growth in the proportion of senior citizens in both countries can be seen in the following 50 years, with the figure for the former reaching a high of roughly 15% before falling slightly and predicted to increase to approximately 23% in 2040, that of the later almost doubled in 1990 and expected to hit a peak at just over 25% at the end of the period.

Japan, on the contrary, with a lower starting point of 5% in 1940 experienced a decrease of around 2% in 1960, followed by a 25-year period of stability before gaining back its 1940's level in the early 2000s. By 2040, It is thought that the percentage of Japanese old population will increase and rocket to peak at around 27%, which slightly outnumbered the figures for the two remaining two nations.