Excel, Copying in-between sheets.

Hi! 

I am working on a paper where I look at different municipalities and population. I have a dataset where I have the name of the municipality in one column and in the two next columns there is how many people how lives there in different time periode. But I need to accumulate many of the different municipalities to one region. So instead of copy every single cell to another sheet, and then summarize it,  do anybody know a function, a course or anything that would help me go faster? 

Best regards! 

Sorry, English isn't my first language.