Weekly Sales forecast sales tracker

I would like a spreadsheet developed that tracks the accuracy of the weekly sales predictions vs. what is actually achieved.

I would like to be able to see this overall with a line graph and on a per-individual basis.

I need this to be able to accommodate the added and removal of sales staff but the overall tracking will not be impacted by individuals leaving just their individual numbers.

I will get the sales team on a weekly basis to provide their sales predictions.

I would like to be able to show the accuracy based on time, i.e this month, last, this quarter, last, this FY, and all time.