Recently I was asked how to subtract time in Excel (time difference) or how to calculate the number of hours between two points in time on different days. Since this was in a reader comment, I gave a brief answer that requires a fuller account here.
How to Create a Drop Down List in Excel with Data Validation
Data Validation is used to define restrictions on what data can or should be entered into a cell. Here we’ll use a List to restrict what values can be entered into a cell.