Writing task 1! Please help me check and correct

The given pie charts display the results of visitor's satisfaction after the recent changes made in the Ashdown Museum. In the following paragraphs, I will delineate visitors opinions before and after the Museum's amendments.

Firstly, It's crystal clear that visitors are really contented with the changes made to the museum.
Where the percentage of people who said they are very satisfied increased to 35% in the last year compared to 15% only in the first visit. In the same manner, the percentage of people who said they are satisfied after the modification raised to 40 visitors instead of 30 in the previous year.

On the other hand, visitors who said they are dissatisfied and very dissatisfied decreased from 40 and 10 before refurbishment to 15 and 5 after refurbishment respectively.

Finally, those who didn't express their opinion remained the same (5 visitors) before and after the change.

To sum up. there was an incredible change in the results of surveys of visitors to Ashdown Museum. After the renovation of the museum, visitors became highly pleased and satisfied.