Dependent List in Excel

Question

My question is , in excel when we create a dependent dropdown we write the formula for the other dropdown dependent on the first one. For example if USA is selected in first

Answer 1

Consider the following,

        

The data validation lists in A2:A10 are based on a List with a Source: of,

=$AA$2:$AA$5

The data validation lists in B2:B10 are based on a List with a Source: of,

=INDEX($AB$2:$AE$6, 0, MATCH($A2, $AB$1:$AE$1, 0))

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