Use a reference to a range or a range name. Uppercase and lowercase text are equivalent. You can put values in ascending order, left to right, by selecting the values and then clicking Sort on the Data menu. Under Sort by, click the row in the list, and then click Ascending. If TRUE or omitted, an approximate match is returned.
Lets setup a quick lookup table based on grades.
We enter the percentage points along with their corresponding letter grades in a range of cells. The next step is to enter our formula. The first parameter is the value we want to lookup. The letter grades are automatically updated as scores are changed or added.