RANK - Returns the rank of a number in a list of numbers. The rank of a number is its size relative to other values in a list. (If you were to sort the list, the rank of the number would be its position.)
Number is the number whose rank you want to find.
Ref is an array of, or a reference to, a list of numbers. Nonnumeric values in ref are ignored.
Order is a number specifying how to rank number.
If order is 0 (zero) or omitted, Microsoft Excel ranks number as if ref were a list sorted in descending order.
If order is any nonzero value, Microsoft Excel ranks number as if ref were a list sorted in ascending order.
RANK gives duplicate numbers the same rank. However, the presence of duplicate numbers affects the ranks of subsequent numbers. For example, in a list of integers sorted in ascending order, if the number 10 appears twice and has a rank of 5, then 11 would have a rank of 7 (no number would have a rank of 6).
For some purposes one might want to use a definition of rank that takes ties into account. In the previous example, one would want a revised rank of 5.5 for the number 10. This can be done by adding the following correction factor to the value returned by RANK. This correction factor is appropriate both for the case where rank is computed in descending order (order = 0 or omitted) or ascending order (order = nonzero value).
In the following example, RANK(A2,A1:A5,1) equals 3. The correction factor is (5 + 1 – 2 – 3)/2 = 0.5 and the revised rank that takes ties into account is 3 + 0.5 = 3.5. If number occurs only once in ref, the correction factor will be 0, since RANK would not have to be adjusted for a tie.