The Excel function: MATCH
The MATCH function searches for a specified item in a range (range: Two or more cells on a sheet. The cells in a range can be adjacent or nonadjacent.) of cells, and then returns the relative position of that item in the range. For example, if the range A1:A3 contains the values 5, 25, and 38, then the formula
returns the number 2, because 25 is the second item in the range.
Use MATCH instead of one of the LOOKUP functions when you need the position of an item in a range instead of the item itself. For example, you might use the MATCH function to provide a value for the row_num argument of the INDEX function.