Table Lookups in Excel

The link below is for an Excel tutorial.  This tutorial shows the use of the “SUMPRODUCT” formula to do a sort of database lookup.  In essence, if you have a table of data and you want Excel to find a value based on matching some information (for example, how many blue widgets were sold in 2012), this formula can do it.  Very similar to VLOOKUP

SUMPRODUCT: Syntax, Usage, Examples and Tutorial by Chandoo.org