Help me - Task 1 ielts

A glance at the graph provided shows the considerable fluctuation between china and the USA fertility in the period from 1920s to 2000s.
It is evidenced that there is a variation about birth rates in both countries, with lows during the 1940s and highs during the 1950s.
In China, the fertility fluctuated from 10% to 15% between 1920s and 1930. There was a sudden decline in 1940s with the lowest peak of 5% and a sharp rise in 1950s with the highest rate of 20%. It, however, decreased stably during the period from 1950s to 2000s.
Birth rate of the USA, meanwhile, varied from 1920s to 1930s with the percentage of 11%, 13 % respectively. It also fell significantly to less than 5% in 1945s and increased rapidly to more than 10% in 1950s. The latter half of the century brought a sustained drop in this figure from 15% to 7%.