Checking for total sum in a column in the Writeback table

For example, I've got the writeback table that consists of 3 rows and 10 columns (the number of rows and columns doesn't matter). 

One of the column is Percent and it must be equal 100% for the rows with the same ID when I do writeback.

So, I would like to have an option where I can configure Percent column on checking total sum,

If sum differ from 100% then the user should get the message that the sum must be 100% when try to writeback data.