Help with Columns and Totals

Hi Everyone,

There maybe a simple solution for this that i may not be seeing but please help with the below:

I have a Few columns that i need to add up to get a total,  then need to show what % each of the Columns contribute to the Total

Example of the table:

Goals: To show the % of C1/ C2/ C3 has on the Total, so if i were to Show a Pie Graph, showing how the pie is split amongst the columns. 

Any help will be appreciated, 

Thanks Everyone