Formula

Hi Gene, thank you for your post, I hope you enjoyed your course, welcome to the forum.
In answer to your question: If a formula displays an error value, such as #DIV/0!, the Trace Error command or button can be used to locate all cells that provide data to the formula, this will quickly allow you to find the problem/s in your worksheet, Auditing is particularly useful when linking worksheet data to other workbooks.
To use Error Tracking follow these steps;
Select the cell that contains the error
Click on the Trace Error button on the Auditing Toolbar (Tools>Auditing>Trace Error)
Red arrows will point from the cells that cause the error to the cell that contains the error. Blue arrows point to the precedents of the cell that causes the error.
Note: to quickly select the cell at the other end of an arrow, double click on the arrow.
I hope that helps, regards Pete