I'm not 100% sure that I understand what you're looking for, but I think if you use:
...in Cell C3 on your 'Summary' sheet, it'll return the total of "4" that you're looking for. If you want a percentage, include '/12' at the end of the formula and format the cell as a percentage. Modify the range for C4, D3, and D4 and you should be all set, right? It'll update the numbers in 'Summary' as the cells are filled in 'Employee Name'. As best I can tell, that's what you're looking for. If I'm wrong, please clarify your request.
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