|There shouldn't be a need for a macro to accomplish your goal.|
Review the information given at this site related to Dependent Data Validation Lists:
Note: The following will make more sense once you are familiar with the instructions found at that site.
You'll need to be creative with your Named Ranges.
For example, a Named Range of France would contain all of the areas in France.
A Named Range of FranceParis would contain the subset of the France areas located in Paris, France.
With your Country drop down in A1 and your State drop down in B1, the List source for the Area drop down would be =INDIRECT(A1&B1).
When B1 is blank, you'll get all the areas in the Named Range found in A1, e.g. France
When B1 contains a state, you'll get just those areas in the Named Range formed by A1&B1 e.g. FranceParis
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