Assume a two column database with names in column A and numbers in column B. Names in column A may be repeated. If a user types a certain name in a cell, a formula should sum the highest three values from column B for that name.
Depending upon the version of MS Excel which you are using, there could be two ways to solve this problem
Solution for MS Excel 2010 and higher versions
If you are using the PowerPivot add-in, then a simple DAX formula can solve this problem.
Solution for all versions of MS Excel
While this solution works for all versions of MS Excel, it uses an array formula (Ctrl+Shift+Enter). Array formulas, if used extensively in the workbook, adversely effect the system’s performance.
You may refer to my solution in this workbook.