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Calculated Columns can be used to take previous grades in the gradebook, as shown in individual-item columns, and aggregate them in order to calculate a final grade total based on specific criteria. Using a Calculated Column can save an instructor considerable work in calculating overall grades throughout the semester, and provide a student with a quick snapshot of their progress. To create a calculated column, navigate to the Gradebook. If you have not already done so, the bottom of the gradebook will have a specialized button prompting you to set up an overall grade. 
You will be given three options to choose from: Points, Weighted, and Advanced. Select the type you wish to create to enter into the column details and click Next. Please note that this decision is not permanent, and can be changed on the following window.
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(Note: This particular calculation space is also accessible after you have already created an overall grade, meaning you can use it to create a gradebook with multiple calculations. This space can be reached from the main gradebook using the Add Item button, then selecting "Add Calculation" from the resulting dropdown.) 
outside of the Overall Grade. How to locate this calculation separately, as well as a more detailed explanation of how to create a calculation, will be in the Creating Calculations In The Gradebook article.)
Regardless of which calculation you select, click 'Save' at the bottom of the page when you have finished customizing your settings. The new external grade will be created, and visible on the top of the Gradebook.
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