The pie charts give information about the percentage of degrees granted in four fields[:] (Computer Science, Business, Law and Medicine) at the National University in 1990, 2000 and 2010.
Clearly, what standout from [on] the graphs shows [is] that degrees granted in Computer Science showed an upward trend over the period while those in Business, in contrast -- Not necessary to include this, consider taking it out., decreased significantly. Interestingly, two other programmes -- Be sure you are using correct spelling based on the country in which you are studying.such as [,] Medicine and Law remained virtually unchanged in the first and last year[,] although there was a change in the middle of the period.
To begin with , in 1990, Computer Science experienced [was] the most popular field which granted degrees, representing a third of all fields. This picture --Use a different word here. went up fairly dramatical[ly] both in [in both] 2000 and 2010, at 40% and 45%[,] respectively. Not surprisingly, Computer Science still witnessed [remained, etc.] in the first [leading] position than other fields . [The] Business programme, on the other hand -- A better word for this phrase is [however], depicted a considerable decline, from 30 percent in 1990 to half of this in the end of year -- Be consistent with how you are writing your percentages. Look up how to write percentages for the specific format your essay needs to be, i.e. APA, MLA, etc., standing as the second most favourite of degrees to be the least ones.
Moving to a more detailed analysis from [of] the graph, [one can see, it clearly, etc.] reveals that Medicine stood the third in 1990, at a quarter. Then, this [This then] increased slightly becoming [raising to] 30% in the next period. However, in 2010, [the] Medicine field went up again, showing a similar proportion like previously [to previous reportings]. Furthermore, this was also the case for Law, which represented [was] the least popular programme at the National University. This one only granted degree less than a fifth over the period.
-- Rephrase this sentence. It is unclear what you are trying to say.
You are off to a good start. Again, make sure you are using proper spelling for your country. Also, you do not need to capitalize the degree fields in your writing. Finally, depending on which format your paper needs to be in, correct and keep consistent the usage of percentage references.
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