Need a crystal ball with a rear view mirror? Watch Excel Video 197. Excel Video 197 starts our discussion of Excel’s Formula Auditing tools. Precedents are like the rear view mirror. Trace Precedents will show you the past, the cells that combine to create the cell you click on. Notice that any precedents that cause an error are shown with a red line instead of the normal blue line. Dependents show the cells that depend on the cell you click on. Tracing dependents is like seeing the future. If you change or delete the value in a given cell, Trace Dependents will show you the cells that will be affected. It’s easy to remove the tracing arrows once you’ve seen what you need to see.
Please note that while Excel has Formula Auditing tools, those tools can’t catch data entry errors (entering 781 instead of 871) or logical errors (adding instead of subtracting last month’s expenses). The tools can show you mathematical errors (dividing by zero) or misspelled functions (SUMM), but they’re no substitute for carefully reviewing important spreadsheets.
