Adding Row Values & Deleting Duplicate Values at the same time

Hi,

I am creating an app for tracking tasks employees due dates & percentages.
I am right now stuck in a situation where my data is clearly added in the system, However the reporting is sort of a havoc. 

There is simple duplication in the reporting manner which I wish to remove. 

All I want to carry out is, Let the system count only the unique values in the "Combined Week & Color" field and post them correctly in "TotalCost" ie. Add the 2 similar values of "Combined Week & Color"

2	Gunsham Lakhiani-14-RED

+

2	Gunsham Lakhiani-14-RED

And display the result in "TotalCost" Field as 1.
I will further be calling the values in this field into another table to make a percent calculation for each employee.

Please assist or let me know if there is any better way to solve this problem.

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Amedha Surve
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