IELTS Task 1 : Describe a graph ( Please help me correct the notebook below, thanks )

The graph indicates the figures about contribution of agriculture, manufacturing, business and financial in the UK economy in the twentieth century from 1900 to 2000.
At first, the general trends were upward ( business and financial ) and downward ( two others sectors ). In 50 first years of the century, agriculture and manufacturing were the main importance elements that affected to the UK economy. Whereas hadn’t been really popular just under 5 %. Fifty years later, agriculture had the highest percent ( above 50 % ) during the period. Likewise, business and financial rose to 5% if compared with 1900. By contrast, there was a slightly decrease at 40 % for manufactory. From 1975 to 2000, there was a big change in contribution among sectors. Could not maintain the highest level like before, contribution percent of agriculture dropped significantly when just had around 12 % and even shorter than two other sectors in comparision. In this year, business and financial developed strongly ending 1975 at above 20% and then continued to grow up to the highest sector.
To sum up, follow development of technology and global changes , decline of agriculture and manufacturing were inevitable. Instead of, business and financial element kept growing steadily over the period. The sector didn’t get the high figure like others , but with a strong development it probably would become the most important in the future.